21.T  YEAR.  1915  218T  EDITION 

STANDARD  WIRING 

FOR 

ELECTRIC  LIGHT  AND  POWER 

AS  ADOPTED  BY 

THE    FIRE    UNDERWRITERS 

OF  THE  UNITED  STATES 


TN  ACCORDANCE  WITH  THE  NATIONAL 
ELECTRICAL  CODE,  WITH  EXPLANATIONS, 
ILLUSTRATIONS  AND  TABLES  NECESSARY 
FOR  OUTSIDE  AND  INSIDE  WIRING  AND  CON- 
STRUCTION FOR  ALL  SYSTEMS,  TOGETHER 
WITH  A  SECTION  ON  HOUSE  WIRING. 


H.  O.  GUSHING,  JR. 

Fellow  )lm.  Inst.  Elecl.  Engrs. 

WITH   THE  CO-OPERATION   OF  THE  NATIONAL  ELECTRIC 
LIGHT  ASSOCIATION  COMMITTEE  ON  WIRING  EX- 
ISTING BUILDINGS,  AND  THE  SOCIETY  FOP 

ELECTRICAL  DEVELOPMENT.     *- 


INDEX   TCT  CONSENTS— PAGE   216 


PUBLISHED  BY 

H.    C.    GUSHING,   JR.,    PULITZER   BLDG,,    NEW   YORK, 
U.  S.  A, 


PREFACE 

THE  Author,  with  the  collaboration  of  Mr.  F. 
E.  Cabot,  Chairman  of  the  Electrical  Com- 
mittee of  the  National  Fire  Protection  Associa- 
tion, and  with  the  co-operation  of  the  National 
Electric  Light  Association  Committee  on  Wiring 
Existing  Buildings,  and  the  Society  for  Electrical 
Development,  has  made  it  his  aim  in  compiling 
the  following  pages  to  set  forth,  as  clearly  as  pos- 
sible, the  essential  rules  and  requirements  for 
safe  and  economical  exterior  and  interior  wiring 
and  construction,  the  object  being  to  standardize, 
as  much  as  possible,  all  work  of  this  nature  and  to 
respectfully  suggest  to  the  Electrical  Engineer, 
Architect,  House-owner,  Contractor  and  Wire- 
man  just  what  is  required  by  Fire  Underwriters 
Inspectors  throughout  the  TJaited  States. 


Copyright,    1915,    by    A.    B.    Gushing. 


THE   GENERATOR 

All  generators,  whether  for  central  station  or 
isolated  lighting  or  power  work,  should  be  located 
in  a  dry  place  so  situated  that  the  surrounding  at- 
mosphere is  cool.  If  the  surrounding  air  is  warm 
it  reduces  the  safe  carrying  capacity  of  the  ma- 
chine, and  is  likely  to  allow  such  temperatures  to 


Proper  installation  of  dynamo  or  motor  on  filled  wooden  base  frame. 

rise  in  the  machine  itself  as  to  burn  out  either 
armature  or  field,  or  both.  A  generator  should 
not  be  installed  in  any  place  whe/e  any  hazardous 
process  is  carried  on,  nor  in  places  where  they 
would  be  exposed  to  inflammable  gases  or  flying 
combustible  materials,  as  the  liability  of  occasional 
sparks  from  the  commutator  or  brushes  might 
cause  more  or  less  serious  explosions. 

3O1 240 


Foundations.  Wherever  it  is  possible,  generat- 
ors should  be  raised  or  insulated  above  the  sur- 
rounding floor  on  wooden  base  frames,  which  should 
be  kept  filled  to  prevent  the  absorption  of  moisture, 
and  also  kept  clean  and  dry.  When  it  is  imprac- 
ticable to  insulate  a  generator  on  account  of  its 
great  weight  or  any  other  reason,  the  Inspection 
Department  of  the  Board  of  Fire  Underwriters 
having  jurisdiction  may,  in  writing,  permit  the  omis- 
sion of  the  wooden  base  frame,  in  which  case  the 
frame  should  be  permanently  and  effectively 
grounded.  Generators  operating  at  a  potential  of 
over  550  volts  should  always  have  their  base  frames 
permanently  grounded.  When  a  frame  is,  grounded 
the  insulation  of  the  entire  system  depends  upon 
the  insulation  of  the  generator  conductors  from  the 
frame,  and  if  this  breaks  down  the  system  is 
grounded  and  should  be  put  in  proper  condition 
at  once. 

Grounding  Generator  Frames  can  be  effectually 
done  by  firmly  attaching  a  wire  to  the  frame  and 
to  any  main  water  pipe  inside  the  building,  on  the 
street  side  of  the  meter,  if  there  is  one.  The  wire 
should  be  securely  fastened  to  the  pipe  by  screwing 
a  brass  plug  into  the  pipe  and  soldering  the  wire 
to  this  plug  or  by  approved  ground  clamps.  When 
the  generator  is  direct  driven  an  excellent  ground  is 
attained  through  the  engine  coupling  and  piping. 

Wherever  high  voltage  machines  have  their 
frames  grounded  a  small  board  walk  should  be 
built  around  them  and  raised  above  the  floor  on 
porcelain  or  glass  insulators,  in  order  that  the  at- 

4 


tendant  may  be  protected  from  shock  when  adjust- 
ing brushes  or  working  about  the  machine. 

Accessibility,  Sufficient  space  should  be  left  on 
all  sides  of  the  generator,  or  motor,  and  especially 
at  the  commutator  end,  so  that  there  may  be  ample 
room  for  removing  armatures,  commutators,  or 
other  parts  at  any  time. 

Circuit  Breakers  and  Fuses.  Every  constant 
potential  generator  should  be  protected  from  ex- 
cessive current  by  a  fuse,  or  equivalent  device  of 
approved  design,  such  as  a  circuit  breaker.  Such 
devices  should  be  placed  on  or  as  near  the  dynamo 
as  possible. 

For  two-wire,  direct-current  generators,  single 
pole  protection  will  be  considered  as  satisfying  the 
above  rule,  provided  the  safety  device  is  located 
and  connected  that  the  means  for  opening  same  is 
actuated  by  the  entire  generator  current  thus  com- 
pletely opening  the  generator  circuit. 

When  two-wire,  direct-current  generators  are 
used  in  conjunction  with  balancer  sets  to  obtain  a 
neutral  for  three-wire  systems,  a  protective  device 
should  be  installed  which  will  operate  and  discon- 
nect the  three-wire  system  should  an  excessive  un- 
balancing of  voltage  occur.  If  a  generator,  not 
electrically  driven,  in  a  two-wire  system  has  one 
terminal  grounded,  the  circuit  breaker  above  men- 
tioned should  be  placed  in  the  g/ounded  lead. 

For  three-wire  direct-current  generators,  either 
compound  or  shunt  wound,  a  safety  device  should 
be  placed  in  each  armature  lead  of  sufficient  ca- 
pacity and  so  arranged  as  to  take  care  of  the  entire 
current  from  the  armature. 


The  safety  devices  for  this  service  should  be  a 
double-pole,  double-coil  overload  circuit-breaker, 
or  a  four-pole  circuit-breaker  connected  in  the  main 
and  equalizer  leads  and  tripped  by  means  of  two 
overload  devices,  one  in  each  armature  lead.  The 
safety  devices  thus  required  should  be  so  inter- 
locked that  no  one  pole  can  be  opened  without  si- 
multaneously disconnecting  both  sides  of  the  arma- 
ture from  the  system. 

Fuses  should  never  be  used  for  this  class  of 
protection. 

In  general,  generators  should  preferably  have  no 
exposed  live  parts  and  the  leads  should  be  well  insu- 
lated and  thoroughly  protected  against  mechanical 
injury.  This  protection  of  the  bare  live  parts 
against  accidental  contact  would  apply  also  to  all 
exposed,  uninsulated  conductors  outside  of  the  gen- 
erator and  not  on  the  switchboard. 

Waterproof  Covers,  though  not  required,  should 
be  provided  for  every  generator  and  motor  and 
placed  over  each  machine  as  soon  as  it  is  shut  down. 
Negligence  in  this  matter  has  caused  many  an  arm- 
ature or  field  coil  to  burn  out,  as  only  a  few  drops 
of  water  are  necessary  to  cause  a  short  circuit,  when 
the  machine  is  started  up  again,  that  might  do  many 
dollars'  worth  of  damage,  to  say  nothing  of  the 
inconvenience  of  having  to  shut  off  light  or  power 
when  it  is  most  needed,  and  for  an  indefinite  length 
of  time. 

Name  Plates.  Every  generator  and  motor  should 
be  provided  with  a  name  plate,  giving  the  maker's 
name,  the  capacity  in  volts  and  amperes  and  nor- 
mal speed  in  revolutions  per  minute.  This  will 


show  exactly  what  the  machine  is  designed  for,  and 
how  it  should  be  run. 

Terminal  blocks  when  used  on  generators  should 
be  made  of  approved  non-combustible  non-absorp- 
tive, insulating  material,  such  as  slate,  marble  or 
porcelain. 

Wiring  from  Generators  to  switchboards  and 
thence  to  outside  lines  should  be  in  plain  sight  or 
readily  accessible,  and  should  be  supported  entirely 
throughout  upon  non-combustible  insulators  (such 
as  glass  or  porcelain)  and  in  no  case  should  any  wire 
come  in  contact  with  anything  except  these  insula- 
tors, and  the  terminals  upon  the  generators  and 
switchboard.  When  it  becomes  necessary  to  run 
these  wires  through  a  wall  or  floor,  the  holes  should 
be  protected  by  some  approved  non-combustible  in- 
sulating tube,  such  as  glass ,  or  porcelain,  and  in 
every  case  the  tube  should  be  so  fastened  that  it 
shall  not  slip  or  pull  out.  Sections  of  any  conduit, 
whether  armored  or  otherwise,  that  are  chopped  off 
for  this  purpose,  should  not  be  used.  All  wires  for 
generator  and  switchboard  work  should  be  kept  so 
far  apart  that  there  is  no  liability  of  their  coming  in 
contact  with  one  another,  nor  of  short  circuit  from 
metallic  tools  used  about  them.  All  wire  used  in 
this  class  of  work  should  be  the  best  quality  of 
"rubber  covered"  (see  page  66).  Bus-bars  on 
switchboards,  may  be  made  of  bare  metal, 
so  that  additional  circuits  may  be  readily 
attached.  They  should  have  ample  carrying 
capacity,  so  as  not  to  heat  with  the  maximum  cur- 
rent likely  to  flow  through  them  under  natural  con- 
ditions. (See  "Capacity  of  Wire  Table/'  page  81.) 


So  much  trouble  in  past  years  has  arisen  from  faulty 
construction    of    switchboards,    and   the   apparatus 
placed   upon   them,   that   strict   requirements   have 
been  necessarily  adopted  by  engineers  as  well  as 
insurance  inspectors,  and  the  following  suggestions, 
are  recommended  by  the  latter ;  although  it  is  advis- 
able, when  possible,  that  all  wires  from  generators  to 
switchboards  be  in  plain  sight  and  readily  accessi- 
ble, wires  from  generator  to  switchboard  may,  how- 
ever, be  placed  in  a  conduit  in  the  brick  or  cement 
pier  on  which  the  generator  stands,  provided  that 
proper  precautions  are  taken  to  protect  them  against 
moisture  and  to  thoroughly  insulate  them  from  the 
pier  or  foundation.     If  lead-covered  cable  is  used, 
no  further  protection  will  be  required,  but  it  should 
not  be  allowed  to  rest  upon  sharp  edges  which  in 
time  might  cut  into  the  lead  sheath,  especially  if  the 
cables  were  liable  to  vibration.    A  smooth  runway 
is   desired.     If   iron   conduit   is   provided,   double 
braided   rubber-covered  wire  will  be  satisfactory. 
In  wiring  switchboards  with  regard  to  their  ground 
detectors,  voltmeters,  pilot  lights,  potential  trans- 
formers or  other  indicating  instruments.     Nothing 
smaller  than  No.   14  B.  &  S.  gage  "rubber  cov- 
ered"  wire   should  be  used,   and  no   such   circuit 
should  carry  over  660  watts.     Such  circuits  should 
be  protected  by  approved  enclosed  fuses.   (See  p. 
124.) 

The  Switchboard  should  be  so  placed  as  to  re- 
duce to  a  minimum  the  danger  of  communicating 
fire  to  adjacent  combustible  material,  and,  like  the 
generator,  should  be  erected  in  a  dry  place  and  kept 
free  from  moisture.  It  is  necessary  that  it  should 


be  accessible  from  all  sides  when  the  wiring  is  done 
on  the  back  of  the  board,  but  may  be  placed  against 
a  brick,  stone  or  cement  wall  when  all  wiring  is  on 
the  face  of  the  switchboard. 

The  board  should  be  constructed  wholly  of  non- 
combustible  material  and  never  built  up  to  the  ceil- 
ing; a  space  of  three  feet,  at  least,  should  separate 
the  top  of  the  board  from  the  ceiling  and  at  least 
eighteen  inches  should  separate  the  wall  from  the 
instruments  or  connections,  when  the  wiring  is  done 
on  the  back  of  the  board.  Every  instrument, 
switch  or  apparatus  of  any  kind  placed  upon  the 
switchboard  should  have  its  own  non-combustible 
insulating  base.  This  is  required  of  every  piece  of 
apparatus  connected  in  any  way  with  any  circuit. 
If  it  is  found  impossible  to  place  the  resistance  box, 
rheostat,  or  regulator,  which  should,  in  every  case, 
be  made  entirely  of  non-combustible  material,  upon 
the  switchboard,  it  should  be  placed  at  least  one 
foot  from  combustible  material  or  separated  there- 
from by  a  non-inflammable,  non-absorptive  insulat- 
ing material.  This  will  require  the  use  of  a  slab  or 
panel  of  non-combustible,  non-absorptive  insulating 
material  such  as  slate,  soapstone  or  marble,  some- 
what larger  than  the  rheostat,  which  should  be 
secured  in  position  independently  of  the  rheostat 
supports.  Bolts  for  supporting  the  rheostat  should 
be  countersunk  at  least  J/6  inch  below  the  surface 
at  the  back  of  the  slab  and  the  holes  over  the  heads 
of  the  bolts  filled  with  insulating  material.  For 
proper  mechanical  strength,  the  slab  should  be  of  a 
thickness  consistent  with  the  size  and  weight  of  the 
rheostat,  and  in  no  case  to  be  less  than  y*>  inch. 

9 


If  resistance  devices  are  installed  in  rooms  where 
dust  or  combustible  flyings  would  be  libale  to  accu- 
mulate on  them,  they  should  be  equipped  with  dust- 
proof  face  plates.  Where  protective  resistances  are 
necessary  in  connection  with  automatic  rheostats, 
incandescent  lamps  may  be  used,  provided  that  they 
do  not  carry  or  control  the  main  current  nor  con- 
stitute the  regulating  resistance  of  the  device. 

When  so  used,  lamps  should  be  mounted  in  por- 
celain receptacles  upon  non-combustible  supports, 
and  should  be  so  arranged  that  they  cannot  have 
impressed  upon  them  a  voltage  greater  than  that  for 
which  they  are  rated.  They  should  in  all  cases  be 
provided  with  a  name-plate,  which  should  be  per- 
manently attached  beside  the  porcelain  receptacle 
or  receptacles  and  stamped  with  the  candle-power 
and  voltage  of  the  lamp  or  lamps  to  be  used  in  each 
receptacle. 

Wherever  insulated  wire  is  used  for  connection 
between  resistances  and  the  contact  device  of  a 
rheostat,  the  insulation  should  be  "slow  burning." 
(See  page  67.)  For  large  rheostats  and  similar 
resistances,  where  the  contact  devices  are  not 
mounted  upon  them,  the  connecting  wires  may  be 
run  together  in  groups  so  arranged  that  the  maxi- 
mum difference  of  potential  between  any  two  wires 
in  any  group  shall  not  exceed  75  volts.  Each  group 
of  wires  should  either  be  mounted  on  no-combust- 
ible, non-absorptive  insulators  giving  at.  least  */£ 
inch  separation  from  surface  wired  over,  or,  where 
it  is  necessary  to  protect  the  wires  from  mechanical 
injury  or  moisture,  be  run  in  approved  conduit  or 

equivalent.     Special  attention  is  again  called  to  the 

10 


fact  that  switchboards  should  not  be  built  down  to 
the  floor,  nor  up  to  the  ceiling,  but  a  space  of  at 
least  ten  or  twelve  inches  should  be  left  between 
the  floor  and  the  board,  and  thirty-six  inches  be- 
tween the  ceiling  and  the  board,  when  possible,  in 
order  to  prevent  possible  fire  from  communicating 
from  the  switchboard  to  the  ceiling,  and  also  to 
prevent  the  forming  of  a  partially  concealed  space 
very  liable  to  be  used  for  storage  of  rubbish  and 
oily  waste.  Where  floor  is  of  brick,  stone  or  con- 
crete, the  switchboard  may  go  to  the  floor,  but  for 
cleanliness  and  safety  space  should  always  be  pro- 
vided when  possible. 

Lightning  Arresters  should  be  attached  to  each 
wire  of  every  overhead  circuit  connected  with  the 
station. 

It  is  recommended  to  all  electric  light  and  power 
companies  that  arresters  be  connected  at  intervals 
over  systems  in  such  numbers  and  so  located  as  to 
prevent  ordinary  discharges  entering  (over  the 
wires)  buildings  connected  to  the  lines  (see  p.  48). 

Arresters  for  Stations  and  Sub-stations  should 
be  located  in  readily  accessible  places  away  from 
combustible  materials,  and  as  near  as  practicable  to 
the  point  where  the  wires  enter  the  building. 

Station  arresters  are  often  placed  in  plain  sight 
on  the  switchboard.  The  switchboard,  however, 
does  not  necessarily  afford  the  only  location  meet- 
ing these  requirements.  In  fact,  if  the  arresters 
can  be  located  in  a  safe  and  accessible  place  away 
from  the  board,  this  should  be  done,  for,  in  case  the 
arrester  should  fail  or  be  seriously  damaged  there 

11 


would  then  be  no  chance  of  starting  arcs  on  the 
board. 

Fire  Extinguishers.  At  least  one,  or  more  if 
the  size  of  the  installation  demands  it,  good  ap- 
proved extinguisher  should  be  in  plain  sight  and 
readily  accessible,  one  which  is  capable  of  extin- 
guishing electrical  fires  or  arcs  without  danger  of 
transmitting  a  shock  to  the  operator  (see  page  194). 

In  all  cases,  kinks,  coils  and  sharp  bends  in  the 
wires  between  the  arresters  and  the  outdoor  lines 
should  be  avoided  as  far  as  possible. 

They  should  be  connected  with  a  thoroughly  good 
and  permanent  ground  connection  by  metallic  strips 
or  wires  having  a  conductivity  not  less  than,  that  of 
a  No.  6  B.  &  S.  copper  wire,  and  these  should  be 
run  as  nearly  in  a  straight  line  as  possible  from  the 
arresters  to  the  earth  connection. 

Ground  wires  from  lightning  arresters  should  not 
be  attached  to  gas-pipes  within  the  buildings. 

It  is  often  desirable  to  introduce  a  choke  coil  in 
circuit  between  the  arresters  and  the  dynamo.  In 
no  case  should  the  ground  wire  from  a  lightning 
arrester  be  put  into  iron  pipes,  as  these  would  tend 
to  impede  the  discharge. 

Unless  a  good  damp  ground  is  used  in  connection 
with  all  lightning  arresters,  they  are  little  better 
than  useless.  Ground  connections  should  be  of  the 
most  approved  construction,  and  should  be  made 
where  permanently  damp  earth  can  be  conveniently 
reached.  For  a  bank  of  arresters  such  as  is  com- 
monly found  in  a  power  house,  the  following  in- 
structions will  be  found  valuable:  First,  dig  a  hole 
six  feet  square  directly  under  the  arresters  until 

12 


permanently  damp  earth  has  been  reached;  second, 
cover  the  bottom  of  this  hole  with  two  feet  of 
crushed  coke  or  charcoal  (about  pea-size)  ;  third, 
over  this  lay  25  square  feet  of  No.  16  copper  plate; 
fourth,  solder  at  least  two  ground  wires,  which 
should  not  be  smaller  than  No.  4,  securely  across 
the  entire  surface  of  the  ground  plate ;  fifth,  now 
cover  the  ground  plate  with  two  feet  of  crushed 
coke  or  charcoal;  sixth,  fill  in  the  hole  with  earth, 
using  running  water  to  settle. 

A  practical  and  effective  method  of  installing  an 
outside  line  arrester  is  shown  on  page  48. 

All  lightning  arresters  should  be  mounted  on 
non-combustible  bases,  and  be  so  constructed  as  not 
to  maintain  an  arc  after  the  discharge  has  passed. 

Testing  of  Insulation  Resistance.  All  circuits 
except  such  as  are  permanently  grounded,  as  de- 
scribed on  pages  45  and  46,  should  be  provided  with 
reliable  ground  detectors.  Detectors  which  indicate 
continuously  and  give  an  instant  and  permanent 
indication  of  a  ground  are  preferable.  Ground 
wires  from  detectors  should  not  be  attached  to  gas 
pipes  within  the  building. 

Where  continuously  indicating  detectors  are  not 
used,  the  circuits  should  be  tested  at  least  or^e 
per  day  (see  page  65),  and  preferably  oftener. 

Data  obtained  from  all  tests  should  be  recorded 
and  preserved  for  examination. 

Storage  or  Secondary  Batteries  should  be  in- 
stalled with  as  much  care  as  generators,  and  in 
wiring  to  and  from  them  the  same  precautions  and 
rules  should  be  adopted  for  safety  and  the  preven- 
tion of  leaks.  The  room  in  which  they  are  placed 

18 


should  not  only  be  kept  dry,  but  exceptionally  well 
ventilated,  to  carry  off  all  fumes  which  are  bound 
to  arise.  The  insulators  for  the  support  of  the 
secondary  batteries  should  be  glass  or  porcelain, 
as  filled  wood  alone  would  not  be  approved.  The 
use  of  any  metal  liable  to  corrosion  should  be 
avoided  in  cell  connections  of  secondary  batteries 
of  the  lead  or  sulphuric  acid  type. 

Care  of  Generators.  A  few  suggestions  as  to 
the  care  of  the  generator,  as  well  as  its  installation, 
may  be  of  value,  and  one  of  the  important  points 
under  this  head  is  that  the  driving  power  should 
have  characteristics  of  steadiness  and  regularity  of 
speed,  and  should  always  be  sufficient  to  drive  the 
generator  with  its  full  load,  in  additions  to  the 
other  work  which  it  may  be  called  upon  to  sustain. 
Unsatisfactory  results  are  always  obtained  if  at- 
tempting to  run  a  generator  on  an  engine  operating 
anything  other  than  its  own  generator  or  gen- 
erators. 

Wooden  bed  plates  are  supplied,  when  ordered, 
for  all  generators,  except  in  the  larger  or  direct- 
connected  machines. 

Most  belt-driven  generators  and  motors  are 
fitted  with  a  ratchet  or  screw  bolt,  so  that  they  may 
be  moved  backward  or  forward  on  the  bed  plate 
in  a  direction  at  right  angles  to  the  armature  shaft. 
By  this  means  the  driving  belt  may  be  tightened  or 
loosened  at  will  while  the  machine  is  in  operation. 
Care  should  be  taken  in  tightening  the  belt  not  to 
bind  the  bearings  of  the  armature  and  force  the  oil 
from  between  the  surface  of  the  shaft  and  boxes. 

u 


Such  practice  will  inevitably  cause  heating  of  the 
bearings  and  consequent  injury. 

Generators  are  usually  assembled,  unless  ordered 
otherwise,  so  that  the  armature  revolves  from  left 
to  right  when  the  observer  faces  the  pulley  end  of 
the  shaft.  All  generators,  however,  may  be  driven 
in  either  direction  by  reversing  the  brush  leads  and 
changing  field  connections. 

The  generator,  if  belt  driven,  is  provided  with  a 
pulley  of  the  proper  size  to  take  care  of  the  power 
necessary  to  drive  it,  and  one  of  different  size 
should  not  be  substituted  unless  approval  be  ob- 
tained from  the  generator  makers. 

When  driving  from  a  countershaft  which,  at  best, 
is  bad  practice,  or  when  belted  directly  to  the  main 
shaft,  a  louse  pulley  or  belt  holder  should  be  used, 
to  admit  of  starting  and  stopping  the  generator 
while  the  shafting  is  running. 

Belts.  A  thin  double  or  heavy  single  belt 
should  be  used,  about  a  half -inch  narrower  than  the 
face  of  the  pulley  on  the  generator.  An  endless 
belt,  one  without  lacing,  gives  the  greatest  steadi- 
ness to  the  lights.  For  proper  length  of  belts  see 
formula  on  page  213. 

All  Bolts  and  nuts  should  be  firmly  screwed 
down.  All  nuts  which  form  part  of  electrical  con- 
nections should  receive  special  attention. 

When  copper  commutator  brrshes  are  used,  al- 
though now  almost  obsolete,  they  are  carefully 
ground  to  fit  the  commutator,  and  they  should  be 
set  in  the  holders  so  as  to  bear  evenly  upon  its 
surface. 

On  machines  where  two  or  more  copper  brushes 

15 


are  supported  on  one  spindle,  the  brushes  on  the 
same  side  of  the  commutator  must  be  set  so  that 
they  touch  the  same  segments  in  the  same  manner. 
The  brushes  on  the  other  side  of  the  commutator 
must  be.  set  so  as  to  bear  on  the  segments  diamet- 
rically opposite.  When  the  brushes  are  not  so  set 
it  is  impossible  to  run  the  machine  without  spark- 
ing. A  convenient  method  of  determining  the 
proper  bearing  point  for  the  brushes. is  to  set  the 
toe  of  one  brush  at  the  line  of  insulation,  dividing 
two  segments  to  the  commutator;  then  count  the 
dividing  lines  for  one-half  the  way  around  the  sur- 
face, and  set  the  other  brush  or  brushes  at  the  line 
diametrically  opposite  the  first.  Thus,  on  a  forty- 
four  segment  commutator,  after  setting  the  tip  of 
one  brush  at  a  line  of  insulation,  count  around 
twenty-three  lines,  setting  the  other  brush  at  the 
twenty-third  line,  thus  bringing  the  tips  directly 
opposite  each  other.  The  angle  which  the  brushes 
form  with  the  surface  of  the  commutator  should  be 
carefully  noted,  and  the  brushes  should  not  be  al- 
lowed to  wear,  so  as  to  increase  or  decrease  this 
angle.  Careless  handling  of  the  machine  is  at  once 
indicated  by  the  brushes  being  worn  either  to  a 
nearly  square  end  or  to  a  long  taper,  in  which  the 
forward  wires  of  the  brush  far  outrun  the  back  or 
inside  wires.  Either  condition  cannot  fail  to  be  at- 
tended with  excessive  wear  of  both  commutator 
and  brushes. 

After  copper  brushes  are  set  in  contact  with  the 
commutator,  the  armature  should  never  be  rotated 
backward.  If  it  is  required  to  turn  the  armature 
back,  raise  the  brushes  from  the  commutator  by  the 

16 


thumb  screw  on  the  holder  provided  for  that  pur- 
pose, before  allowing  such  rotation. 

Carbon  Brushes  are  now  almost  universally 
used  and  require  little  or  no  adjustment  or  care 
other  than  keeping  them  clean. 

Bearings.  See  that  the  bearings  of  the  ma- 
chine are  clean  and  free  from  grit,  and  that  the  oil 
reservoirs  are  rilled  with  a  good  quality  of  lubricat- 
ing oil. 

The  Oil  Reservoirs  should  always  be  axamined 
before  starting,  and  all  loose  grit  removed.  The  oil 
should  all  be  drawn  off  at  the  end  of  each  day's 
run  for  the  first  three  or  four  days  and  filtered, 
after  which  it  can  be  assumed  that  any  grit  has 
been  carried  off  with  the  filtration,  and  it  will  only 
be  necessary  to  add  a  little  fresh  oil  once  in  seven 
to  ten  days.  These  instructions  apply  only  to  ma- 
chines using  loose  ring  oilers  attached  to  each  end 
of  the  armature  shaft. 

In  starting  up  a  Generator  or  motor  fill  the  oil 
reservoirs  and  see  that  the  oiling  rings  are  free  to 
move.  In  the  case  of  generators  fitted  with  oil 
cups,  start  the  oil  running  at  a  moderate  rate.  Too 
little  oil  will  result  in  heating  and  injury  of  the 
bearing;  but,  on  the  other  hand,  excessive  lubrica- 
tion is  unnecessary,  wasteful,  and  sometimes  pro- 
ductive of  harm. 

When  the  generator  is  ready  to  be  started,  place 
the  driving  belt  on  the  pulley  on  the  armature  shaft, 
and  then  slip  it  from  the  loose  pulley  or  belt  holder 
on  to  the  driving  pulley  on  the  counter-shaft. 
Tighten  the  belt,  by  means  of  the  ratchet  on  the 
bed  plate,  just  sufficiently  to  keep  it  from  slipping. 


Care  should  be  taken  not  to  put  more  pressure  than 
is  necessary  on  bearings ;  carelessness  in  this  respect 
is  often  followed  by  heating  of  the  boxes,  and  pos- 
sible permanent  injury. 

The  brushes  may  now  be  let  down  upon  the  com- 
mutator, if  copper  brushes  are  used. 

Move  the  brushes  slowly  backward  or  forward 
by  means  of  the  yoke  handle,  until  there  is  no 
sparking  at  the  lower  brushes.  Clamp  the  yoke  in 
this  position.  If  the  top  brushes  then  spark,  move 
them  slightly,  one  at  a  time,  forward  or  backward  in 
the  brush  holder  until  their  non-sparking  point  is 
found. 

The  spring  pressure  exerted  upon  the  commuta- 
tor brushes  should  be  just  sufficient  to  produce  a 
good  ^contact  without  causing  cutting.  If  the 
brushes  cut,  the  commutator  must  be  smoothed  by 
the  use  of  fine  sandpaper,  NOT  emery  cloth. 

The  generator  should  run,  without  load,  at  the 
speed  given  by  the  manufacturer,  and  this  speed 
should  be  closely  maintained  under  all  conditions. 
In  the  case  of  generators  for  incandescent  light- 
ing, any  increase  of  speed,  above  that  given,  nat- 
urally increases  the  voltage  which  is  prejudicial 
to  the  life  of  the  lamps,  while  a  variation  below 
causes  unsatisfactory  light  (see  table,  page  116). 

Before  starting  a  direct  current  generator,  for  the 
first  time,  if  to  be  run  in  connection  with  another 
or  more  generators,  it  should  be  tested  for  polarity. 
TJiis  may  be  done  by  holding  a  small  pocket  compass 
near  the  field  or  pole  piece.  If  the  dynamo  is  con- 
nected to  be  run  in  multiple  with  another  machine 
and  happens  to  be  polarized  wrong,  it  can  be  given 

18 


the  right  polarity  by  lifting  the  brushes  from  the 
commutator,  closing  the  field  switch,  and  then  clos- 
ing the  double-pole  switch  used  to  throw  it  in  mul- 
tiple with  the  other  machine,  which  is  supposed  to 
be  now  running.  After  the  current  has  been  al- 
lowed to  pass  through  the  fields  for  a  few  moments, 
the  double-pole  switch  can  be  thrown  open,  and  if  a 
test  with  the  compass  is  again  made  the  polarity 
will  be  found  to  be  the  same  as  the  other,  machine, 
or  machines,  and  is  ready  to  be  started  in  the  usual 
manner  in  multiple.  (See  page  37.) 

If  the  dynamo  is  to  be  used  in  series  with  an- 
other on  the  three-wire  system,  and  is  found  to  be 
polarized  wrong,  it  can  be  given  the  right  polarity 
by  making  a  temporary  connection  from  the  posi- 
tive brush  of  the  new  machine  to  the  positive  brush 
of  the  machine  already  in  operation;  and  also  a 
temporary  connection  from  negative  brush  to  neg- 
ative brush,  having  first  raised  the  brushes  from  the 
commutator  and  closing  the  field  switch.  Keep  this 
connection  for  a  few  minutes,  then  open  the  field 
switch  and  break  the  temporary  connections. 

Another  test  with  the  compass  will  show  that  the 
polarity  of  the  machine  is  now  correct,  and  the 
dynamo  is  ready  to  be  started  in  the  usual  manner 
in  series.  (See  page  37.) 

Assuming  that  the  lamps  and  lines  are  all  ready, 
the  following  precautions  should  be  observed  when 
starting  the  dynamo : 

Be  very  careful  that  the  brushes  are  properly  set 
and  diametrically  opposite  each  other,  as  already 
stated. 

19 


Be  sure  that  all  connections  are  securely  made, 
and  all  nuts  or  connections  firmly  set. 

In  cases  where  two  or  more  dynamos  are  con- 
nected in  multiple  by  the  use  of  the  equalizing  con- 
nection, care  should  be  taken  that  the  circuit  wires 
from  both  positive  brushes  be  connected  to  the  same 
side  of  the  main  line,  while  those  from  the  negative 
are  connected  to  the  other  side. 

A  neat  arrangement  of  the  equalizing  connection 
can  be  made  by  using  triple-pole  switches  on  the 
switchboard,  instead  of  double-pole  switches,  and 
making  the  equalizing  connections  through  the  cen- 
ter pole  of  the  switch,  instead  of  running  a  cable 
direct  from  one  dynamo  to  the  other.  This  method 
is  especially  desirable  where  three  or  more  dynamos 
are  run  in  multiple. 

When  dynamos  are  connected  in  series,  as  in  the 
cases  where  the  three-wire  system  is  in  use,  the 
leading  wire  from  the  positive  brush  of  one  ma- 
chine is  connected  to  the  negative  brush  of  the 
other.  The  other  two  brushes  (negative  and  pos- 
itive) are  connected  to  the  two  main  wires  on  the 
outside  of  the  system,  while  the  third  or  neutral 
wire  is  connected  to  the  conductor  between  the  two 
generators. 

Keep  all  commutator  and  brush  holder  insula- 
tions free  from  dust,  gritty  substances  and  oil. 
They  should  be  carefully  cleaned  once  a  day. 

If  any  of  the  connections  of  the  machine  become 
heated,  examination  will  show  that  the  metal  sur- 
faces are  not  clean  or  not  in  perfect  contact. 

The  Commutator  should  be  kept  clean  and  al- 
lowed to  polish  or  glaze  itself  while  running.  No 

20 


oil  is  necessary  unless  the  brushes  cut,  and  then  only 
at  the  point  of  cutting.  A  cloth  slightly  greased 
with  vaseline  is  best  for  the  purpose.  Never  use 
sandpaper  on  the  commutator  without  first  lifting 
the  brushes.  Otherwise,  the  grit  will  stick  to  the 
brushes  and  cut  the  commutator. 

Hot  Bearings.  The  most  natural  thing  to  do 
is  to  shut  the  machine  down,  but  this  should  never 
be  done  until  the  following  alternatives  have  been 
tried  and  have  failed: 

First — Lighten  the  load. 

Second — Slacken  the  belt. 

Third — Loosen  the  caps  on  the  boxes  a  little. 

Fourth- — Put  more  oil  in  bearings. 

Fifth — If  all  the  above  fail  to  remedy  the  heat- 
ing, use  a  heavy  lubricant,  such  as  vaseline  or  cyl- 
inder oil.  Should  the  heating  then  diminish,  the 
shaft  must  be  polished  with  crocus  cloth  and  the 
boxes  scraped  at  the  first  opportunity. 

Sixth — Under  no  conditions  put  ice  upon  the 
bearings  unless  you  are  perfectly  familiar  with 
such  a  procedure. 

Seventh — If  it  is  absolutely  necessary  to  shut 
down,  get  the  belt  off  as  soon  as  possible,  keeping 
the  machine  revolving  meanwhile  in  order  to  pre- 
vent sticking,  and  at  the  same  time  take  off  the 
caps  of  the  bearings.  Do  not  stop  the  flow  of  oil 
to  the  bearings.  When  the  caps  "have  been  taken 
off,  stop  the  machine  and  get  the  linings  out  imme- 
diately, and  allow  them  to  cool  in  the  air.  Do  not 
throw  the  linings  into  cold  water,  as  it  would  be 
apt  to  spring  them. 

Scraping  should  be  done  only  by  an  experienced 
21 


person,  otherwise  the  linings  may  be  ruined.  Polish 
the  shaft  with  crocus  cloth,  or,  if  badly  cut,  file 
with  a  very  fine  file,  and  afterward  polish,  with 
crocus.  Wipe  the  shaft,  as  well  as  the  boxes,  very 
carefully,  as  perhaps  grit  has  been  the  cause  of  the 
hot  box.  Inspect  the  bearings,  see  that  they  are  in 
.line,  that  the  shaft  has  not  been  sprung,  and  that 
the  oil  collar  does  not  bear  against  the  box. 

Oily  Waste  should  be  kept  in  approved  metal 
cans  (made  entirely  of  metal,  with  legs  raising  them 
at  least  three  inches  above  the  floor,  and  with  self- 
closing  covers)  and  removed  daily. 

Attendance.     A  competent  man  should  always 
be  kept  on  duty  where  generators  are  operating. 
MOTORS. 

The  Installation  of  Motors.  All  direct-current 
motors  for  550  volts  or  less,  should  be  insulated  on 
wooden  floors  or  base  frames,  which  should  be  kept 
filled  to  prevent  absorption  of  moisture;  and  kept 
clean  and  dry.  Where  frame  insulation  is  imprac- 
ticable the  Inspection  Department  having  jurisdic- 
tion may,  in  writing,  permit  its  omission,  in  which 
case  the  frame  should  be  permanently  and  effect- 
ively grounded.  The  use  of  motors  operating  at  a 
potential  in  excess  of  550  volts  will  only  be  ap- 
proved when  every  practicable  safeguard  has  been 
provided.  They  should  have  no  exposed  live  metal 
parts  and  their  base  frames,  in  every  case,  should 
be  permanently  and  effectively  grounded,  as  in  the 
case  of  generators.  Plans  for  such  installations 
should  be  submitted,  for  approval,  to  the  Inspection 
Department  having  jurisdiction  before  any  work 
is  begun. 

22 


A  high-voltage  machine  which,  on  account  of 
great  weight  or  for  other  reasons,  cannot  have  its 
frame  insulated,  should  have  its  frame  permanently 
grounded  and  should  be  surrounded  with  an  insu- 
lated platform.  This  may  be  made  of  wood, 
mounted  on  insulating  supports,  and  so  arranged 
that  a  man  must  stand  upon  it  in  order  to  touch 
any  part  of  the  machine.  Motors  operating  at  a 
potential  of  550  volts  or  less  should  be  wired  with 
the  same  precautions  as  required  for  lighting  wires 
carrying  a  current  of  the  same  volume. 

Motors  operating  at  a  potential  between  550  and 
3,500  volts  should  be  wired  with  approved  multiple 
conductor,  metal  sheathed  cable  in  approved  metal 
conduit  firmly  secured  in  place.  The  metal  sheath 
should  be  permanently  and  effectively  grounded,  and 
the  construction  and  installation  of  the  conduit 
should  conform  to  rules  for  interior  conduits,  ex- 
cept that  at  outlets  approved  outlet  bushings  should 
be  used  in  place  of  the  outlet  box. 

The  leads  or  branch  circuits  from  the  source  of 
supply  should  be  designed  to  carry  a  current  at 
least  25  per  cent,  greater  than  that  required  by  the 
rated  capacity  of  the  motor  to  provide  for  the  in- 
evitable excess  current  used  by  the  motor  at  times, 
especially  when  starting,  without  overfusing  the 
wires.  Where  the  wires  would  be  ovtrfused,  in 
order  to  provide  for  the  starting  current,  as  in  the 
case  of  many  of  the  alternating  current  motors,  the 
wires  should  be  of  such  size  as  to  be  properly  pro- 
tected by  these  larger  fuses. 

The  insulation  of  the  several  conductors  for  high 
voltage  motors,  where  leaving  the  metal  sheath  at 


23 


outlets,  should  be  thoroughly  protected  from  mois- 
ture and  mechanical  injury.  This  may  be  accom- 
plished by  means  of  a  pot  head  or  some  equivalent 
device.  The  conduit  should  be  substantially 
bonded  to  the  metal  casings  of  all  fittings  and  appa- 
ratus connected  to  the  inside  high  tension  circuit. 
It  would  be  much  preferable  to  make  the  conduit 
system  continuous  throughout  by  connecting  the 
conduit  to  fittings  and  motors  by  means  of  screw 
joints,  and  this  construction  is  strongly  recom- 
mended wherever  practicable. 

High  voltage  motors  should  preferably  be  so 
located  that  the  amount  of  inside  wiring  will  be 
reduced  to  a  minimum. 

The  Inspection  Department  having  jurisdiction 
may  permit  the  wire  for  high  voltage  motors  to  be 
installed  according  to  the  general  rules  for  high 
voltage  systems  when  the  outside  wires  directly 
enter  a  motor  room.  Under  these  conditions  there 
would  generally  be  but  a  few  feet  of  wire  inside  the 
building  and  none  outside  the  motor  room. 

The  motor  and  the  rheostat  should  be  protected 
by  a  cutout  or  circuit  breaker,  and  controlled  by  a 
switch  (see  illustrations  on  pages  33  to  37),  said 
switch  plainly  indicating  whether  "on"  or  "off." 
Small  motors  may  be  grouped  under  the  protection 
of  a  single  set  of  fuses,  provided  the  rated  capacity 
of  the  fuses  does  not  exceed  6  amperes.  Where 
one-fourth  horse-power  or  less  is  used  on  circuits 
where  the  voltage  does  not  exceed  300,  a  single- 
pole  switch  will  be  accepted.  The  switch  and  rheo- 
stat should  be  located  within  sight  of  the  motor, 
except  in  such  cases  where  special  permission  to 

24 


locate  them  elsewhere  is  given,  in  writing,  by  the 
Inspection  Department  having  jurisdiction. 

In  connection  with  motors  the  use  of  circuit- 
breakers,  automatic  rheostats  with  automatic  un- 
der-load  switches  is  recommended,  wherever  it  is 
possible  to  install  them. 

Where  the  circuit-breaking  device  on  the  motor- 
starting  rheostat  disconnects  all  wires  of  the  circuit, 
the  switch  called  for  in  this  section  may  be  omitted. 
Overload-release  devices  on  motor-starting  rheostats 
should  not  be  considered  to  take  the  place  of  the 
cut-out  required  by  this  section  if  they  are  inopera- 
tive during  the  starting  of  the  motor. 

The  switch  is  necessary  for  entirely  disconnecting 
the  motor  when  not  in  use,  and  the  cut-out  to  pro- 
tect the  motor  from  excessive  currents  due  to  acci- 
dents or  careless  handling  when  starting.  An 
automatic  circuit-breaker  disconnecting  all  wires  of 
the  circuit  may,  however,  serve  as  both  switch  and 
cut-out.  The  use  of  circuit-breakers  with  motors 
is  recommended,  and  may  be  required  by  the  In- 
spection Department  having  jurisdiction. 

To  be  safe,  a  rheostat  should  have  as  great  a 
carrying  capacity  as  the  motor  itself,  or  else  the  arm 
should  have  a  strong  spring-throw7  attachment,  so 
arranged  that  it  cannot  remain  at  any  intermediate 
position  unless  purposely  held  there.  See  cut  on 
page  27. 

Auto  starters,  unless  equipped  with  tight  casings 
enclosing  all  current-carrying  parts,  should  be 
treated  about  the  same  as  knife  switches,  and  in  all 
.wet,  dusty  or  linty  places,  should  be  enclosed  in 
dust-tight,  fireproof  cabinets.  If  a 'special  motor 

25 


room  is  provided,  the  starting  apparatus  and  safety 
devices  should  be  included  within  it.  Where  there 
is  any  liability  of  short  circuits  across  their  exposed 
live  parts  being  caused  by  accidental  contacts,  they 
should  either  be  enclosed  in  cabinets,  or  else  a  rail- 
ing should  be  erected  around  them  to  keep  unau- 
thorized persons  away  from  their  immediate 
vicinity. 

Motors  should  not  be  run  in  series-multiple  or 
multiple-series,  except  on  constant-potential  sys- 
tems, and  then  only  by  special  permission  of  the 
Inspection  Department  having  jurisdiction. 

Like  generators,  they  should  be  covered  with  a 
waterproof  cover  when  not.  in  use,  and,  if  neces- 
sary, should  be  incjosed  in  an  approved  case. 

When  it  is  necessary  to  locate  a  motor  in  the 
vicinity  of  combustibles  or  in  wet  or  very  dusty 
or  dirty  places,  it  is  generally  advisable  to  enclose 
it  in  a  dust-tight  fireproof  cabinet. 

Such  enclosures  should  be  readily  accessible  and 
sufficiently  ventilated  to  prevent  an  excessive  rise 
of  temperature.  The  sides  should  preferably  be 
made  largely  of  glass,  so  that  the  motor  may  be  al- 
ways plainly  visible.  This  lessens  the  chance  of  its 
being  neglected,  and  allows  any  derangement  to  be 
more  readily  noticed.  k 

The  use  of  the  enclosed  type  of  motor  is  recom- 
mended in  dusty  places,  being  preferable  to  wooden 
boxing. 

Motors,  when  combined  with  ceiling  fans,  should 
be  hung  from  insulated  hooks,  or  else  there  should 
be  an  insulator  interposed  between  the  motor  and 
its  support. 

26 


Every  motor  should  be  provided  with  a  name- 
plate,  giving-  the  maker's  name,  the  capacity  in  volts 
and  amperes,  and  the  normal  speed  in  revolutions 
per  minute. 

Starting  and  Stopping  Motors  (Direct  Current) 
One  rule  at  all  times  to  be  remembered  in  starting 
and  stopping  motors  is,  switch  first,  rheostat  last, 
which  means,  in  starting,  close  the  .switch  first,  and 
then  gradually  cut  out  all  resistance  as  the  motor 
speeds  up.  To  stop  the  motor  open  the  switch  first 
and  then  cut  in  all  the  resistance  of  the  rheostat 


Motor     Starting    Rheostat     or    "Resistance    Box"    with    No-Voltage 

Release.      Slate   front  carries   lever,   contacts    and   release   spool, 

mounted    on    a    ventilated    box    of    pressed    steel    which 

serves   as   a  container   for   the   resistance. 

which  is  in  series  with  the  motor  armature.  When 
starting  any  new  motor  for  the  first  time,  see  that 
the  belt  is  removed  from  the  pulley  and  the  motor 
started  with  no  load.  Never  keep  the  rheostat 
handle  on  any  of  its  coils  longer  than  a  moment, 
as  they  are  not  designed  to  regulate  the  speed  of  the 
motor,  but  to  prevent  too  large  a  flow  of  current 
into  the  armature  before  the  latter  has  attained  its 
full  speed. 

27 


The  illustration  (p.  27)  shows  a  rheostat  which  is 
designed  to  automatically  protect  the  armature  of 
a  motor.  The  contact  arm  is  fitted  with  a  spring 
which  constantly  tends  to  throw  the  arm  on  the 
"off-point"  and  open  the  circuit,  but  is  prevented 
from  so  doing,  while  the  motor  is  in  operation,  by 
the  small  electro-magnet,  shown  on  the  face  of  the 
rheostat,  which  consists  of  low  resistance  coil  con- 
nected in  series  with  the  field  winding  of  the  motor. 
This  magnet  holds  the  contact  arm  of  the  rheostat 
in  the  position,  allowing  the  maximum  working  cur- 
rent to  flow  through  the  armature  while  it  is  in 
operation. 

If,  for  some  reason  or  other,  the  current  sup- 
plied to  the  motor  be  momentarily  cut  off,  the  speed 
of  the  armature  generates  a  counter  current  which 
also  tends  to  hold  the  arm  in  position  as  long  as 
there  is  any  motion  to  the  motor  armature,  but  as 
soon  as  the  armature  ceases  to  revolve  all  current 
ceases  to  flow  through  the  electromagnet,  thereby 
releasing  the  rheostat  handle,  which  flies  back  to 
the  "off"  point,  as  shown  in  the  illustration,  and 
the  motor  armature  is  out  of  danger.  Such  a  de- 
vice is  of  great  value  where  inexperienced  men  have 
to  handle  motors,  and  are  unaware  that  the  first 
thing  to  be  done  when  a  motor  stops  for  any  reason 
whatever  is  to  open  the  circuit,  and  then  cut  in  all 
the  resistance  in  the  rheostat  to  prevent  too  large 
an  in-rush  of  current  when  the  motor  is  started  up 
again. 

The  Circuit  Breaker  for  under  and  over  loads  is 
also  a  most  valuable  protection  in  such  cases. 


Motor    Wiring    Formulae — (Direct    Current). 

To  find  the  proper  size  of  wire  for  direct-current 
motors  proceed  as  follows : 
e  —  voltage  of  motor, 
d  =  single  distance  from  generator  to  motor  in 

feet. 

v  =  volts  loss  in  lines, 
k  =  efficiency  of.motor.  (See  table  below.) 
10.8  —  Resistance  in  ohms  of  a  wire  I  ft  long 
and  .001  inch  diameter.    Then 
in  size  or  wire  circular  mils  (cm) 

horsepower  X  746  X  2d  X  10.8 
c.m.  =  - 

e  X  v  ;X  k 

horsepower  X   d  X    16113.6 
or  simplified  cm  •_—  - 

e  X  v  X  k 

Compare  the  size  of  wire  thus  found  with  that  al- 
lowed by  the  underwriters  for  full  load  current  of 
motor,  -|-  25%.  If  it  be  smaller  it  must  be  increased 
to  at  least  that  figure  to  be  approved  and  the  re- 
sulting lower  line  loss  accepted.  (See  table,  p.  81.) 

THE    AVERAGE    MOTOR    EFFICIENCY     (K). 

I  h.p.  and  under 75  per  cent. 

3  h.p.  to  5  h'.p 80  per  cent. 

5  .h.p.  to  10  h.p 85  to  90  per  cent. 

Over    10   h.p 90  per  cent. 

The  tables  and  examples  worked  out  on  pages 
52-54  and  69-71  will  give  the  desired  results,  in 
many  cases  of  smaller  installations  without  having 
to  use  the  above  direct  current  formulae. 

29 


CURRENT  REQUIRED  BY  MOTOR 

(Direct  Current.) 

To  find  current  required  by  'a  motor  when  the 
horse-power,  efficiency  and  voltage  are  known,  use 
the  following  formula  : 
Let  C  —  current  to  be  found. 

H.  P  —  horse-power  of  motor. 
E  —  voltage  of  motor  circuit. 
K  —  efficiency  of  motor  intper  cent. 
H.  P.  X  746  X  ioo 


E  X  K 

The  table  of  "amperes  per  motor"  given  on  the 
following  page,  will,  in  many  cases,  prevent  the 
trouble  of  working  out  the  above  formula. 

By  adding  the  volts  indicated  in  the  (page  32) 
table  to  the  voltage  of  the  lamp  or  motor,  the  re- 
sult shows  the  voltage  at  the  dynamo  for  losses  in- 
dicated. Thus,  10  per  cent,  on  no  volt  system  is: 
12.22  volts  added  to  no  equal  122.22,  showing  that 
the  dynamo  must  generate  122.22  volts  to  take  care 
of  a  10  per  cent,  loss  in  the  line  (for  A.  C.,  see  pp. 
70-78). 

SIZES    OF   FUSES,    IN  AMPERES,    FOR   MOTORS    EQUIPPED 
WITH    OVERLOAD    STARTING  RHEOSTATS. 

Horsepower.     115  Volts.     230  Volts.     500  Volts. 


0.5 

8 

4 

2 

1 

15 

8 

4 

2 

30 

15 

7 

3 

40 

20 

10 

4 

50 

25 

12 

5 

60 

30 

15 

7.5 

90 

45 

20 

10 

115 

60 

25 

15 

175 

90 

40 

20 

225 

115 

50 

25 

300 

150 

60 

30 

350 

175 

76 

35 

400 

200 

90 

40 

450 

225 

100 

50 

600 

300 

125 

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An  approved  installation  in  every  detail,  and  wiring  connection*  for 

fthunt-wound,  four-pole  motor,  using  two  enclosed  fuse* 

instead  of  circuit  breaker. 


IRON    FRAME 
STARTING  RHEOSTAT 


An  approved   installation  in  every  detail  and  wiring  connections  for 

shunt-wound  multipolar  slow  speed  ceiling  motor  for  direct 

Connection  to  line  shafting,  using  both  circuit 

bieaker  and  double-pole  fuse  cut-out. 


An  approved   installation    in    every    detail,    and   wiring   connections, 

for  shunt-wound  bipolar  motor,  using  circuit  breaker 

instead  of  double-pole  fuse  cut-out. 


86 


CONNECTIONS  FOR  DIRECT  CURRENT  MOTORS 


SERIES  MOTOR. 
4-POLE 


SHUNT  MOTOR 
4-POLE 


36 


CONNECTIONS  FOR  DIRECT  CURRENT  DYNAMOS. 


Rheostat 


1 


Rheostat 


THREE  WIRE  DISTRIBUTION 


^heostat 


Rheostat 


at 


i ' 4 

[ Equalizer T 


r  c  * 


MULTIPLE  JDISTRIBUTION-TWO  WIRE 


37 


CONNECTIONS  FOR  DIRECT  CURRENT 
MOTORS  &  DYNAMOS 

C    °-  P-  A 

Enclosed 
fuse 


COMPOUND  MOTOR 
2  POLE 


COMPOUND  DYNAMO 
2-POLE 


COMPOUND  MOTOR 
4- POLE 


COMPOUND  DYNAMO 
'l-POLE 


OUTSIDE  WIRING  AND 
CONSTRUCTION 

Service  Wires  (those  leading  from  the  outside 
main  wire  to  the  buildings  and  attached  to  same) 
should  be  "Rubber  Covered,''  as  described  on  page 
66,  under  that  heading. 

Line  Wires,  other  than  service  wire,  should 
have  an  approved  "weatherproof"  covering.  (See 
page  67.) 

Bare  Wires  may  be  used  through  uninhabited 
and  isolated  territories  free  from  all  other  wires,  as 
in  such  places  wire  covering  would  be  of  little  use, 
as  it  is  not  relied  on  for  pole  insulation. 


For  Insulated   Wires.  For   Bare   Wire   or   Cable. 

Insulator   Clamps. 

Tie  Wires  should  have  an  insulation  equal  to 
that  of  the  conductors  they  confine,  within  city 
limits,  or  some  permanent  clamp  that  wilt  not  injure 
the  insulation. 

Space  between  Wires  for  outside  work,  whether 
for  high  or  low  tension,  should  be  at  least  one  foot, 
and  care  should  be  exercised  to  prevent  any  possi- 
bility of  a.  cross  connection  by  water.  Wires  should 
never  come  in  contact  with  anything  except  their 
insulators.- 

Roof  Structures.  If  it  should  become  neces- 
sary to  run  wires  over  a  building,  the  wires  should 


39 


be  supported  on  racks  which  will  raise  them  from 
7  to  12  feet  above  flat  roofs,  as  shown  on  page  43, 
or  at  least  one  foot  above  the  ridge  of  pitched  roofs, 
and  should  be  strongly  made. 

Guard  Arms.  Whenever  sharp  corners  are 
turned,  each  cross  arm  should  be  provided  with  a 
dead  insulated  guard  arm,  or  guard  iron,  to  pre- 
vent the  wires  from  dropping  down  and  creating 
trouble,  should  their  insulating  support  give  way. 
(See  Fig.  2,  page  64.) 

Petticoat  Insulators  (See  illustrations  on  page 
41)  should  be  used  exclusively  for  all  outside  work, 
and  especially  on  cross  arms,  racks,  roof  structures 
and  service  blocks.  Porcelain  knobs,  cleats  or  rub- 
ber hooks  should  never  be  used  for  this  heavy 
outside  work.  In  fact,  rubber  hooks  are  not  now 
approved  for  any  form  of  electric  light  or  power 
work. 


The     Dossert     Solderless     Cable    Connector    approved    for    use     on 
stranded   wires   and   cables    without   the   use   of   solder. 

Splicing  of  two  pieces  of  wire  or  cable  should 
be  so  done  as  to  be  mechanically  and  electrically 
secure  without  solder.  They  should  then  be  sol- 
dered, unless  made  with  some  form  of  approved 
splicing  device.  This  ruling  applies  to  joints  and 
splices  in  all  classes  of  wiring.  All  joints  whether 
soldered  or  made  with  an  approved  splicing  device 
should  be  covered  with  an  insulation  equal  to  that 
of  the  conductors. 

40 


6000   Volts  4000   Volts  15000   Volts 

Types  of  Petticoat  Insulators  for  high  voltages. 


Construction  Work — Tree  Insulation. 


41 


Tree  Wiring.  Whenever  a  line  passes  through 
the  branches  of  trees,  it  should  be  properly  sup- 
ported by  insulators,  as  shown  on  page  41,  to  pre- 
vent the  chafing  of  the  wire  insulation  and  ground- 
ing the  circuit. 

The  tree  insulators  shown  on  the  previous  page 
have  proved  themselves  to  be  the  most  practical 
and  permanent  insulators  for  all  kinds  of  tree  con- 
struction, allowing  the  free  swaying  of  limbs 
without  chafing  the  insulation  of  the  wires. 

Service  Blocks  which  are  attached  to  buildings 
should  have  at  least  two  coats  of  waterproof  paint 
to  prevent  the  absorption  of  moisture. 

Size  of  Wire.  To  find  the  required  size  of  wire 
in  circular  mils  for  any  alternating  current  system, 
to  carry  any  required  current  any  distance  at  any 
voltage  and.  with  any  required  loss,  use  the  for- 
mulae and  examples  on  pages  69  to  78,  and  for  di- 
rect currents  the  formulae  on. pages  198  and  199. 
When  possible,  however,  refer  to  tables  No.  I  or 
No.  2  on  pages  52  and  69,  respectively,  as  they  will 
be  found  much  simpler  when  within  their  limita- 
tions. 

Service  Wires.  Where  service  wires  enter  a 
building  they  should  have  drip  loops  outside  and 
the  holes  through  which  the  conductors  pass  should 
be  bushed  with  non-combustible,  non-absorptive  in- 
sulating tubes,  such  as  glass  or  porcelain,  slanting 
upward  toward  the  inside. 

Where  metal  conduit  is  used  the  conduit  should 
be  curved  downward  at  its  outer  end  and  carefully 
sealed  or,  a  much  better  method  is  to  use  an  ap- 


proved    service-head    to    prevent   the    entrance    of 
moisture.     (See  illustration  below.) 

The  inner  end  should  extend  to  the  service  cut- 
out. If  a  cabinet  is  used  the  conduit  should  be 
properly  carried  within  the  cabinet. 


G-V  Universal — An  Approved  Service  Head  for  Service  or  Entrance 
Wires.    It  may  be  used  in  either  a  Horizontal  or  Vertical  Position. 

Telegraph  and  Telephone  wires  should  nevei , 
be  placed  on  the  same  cross  arm  with  light  or 
power  wires,  especially  when  alternating  currents 
are  used,  as  trouble  will  arise  from  induction,  un- 
less expensive  special  construction,  such  as  the 
transposing  of  the  lighting  circuits,  be  resorted  to 
at  regular  intervals.  Even  under  these  conditions 
it  is  bad  practice,  as  an  accidental  contact  between 
the  lighting  or  power  circuit  might  result  in  start- 
ing a  fire  in  the  building  to  which  the  telephone  line 
is  connected.  If,  however,  it  is  necessary  to  place 
telegraph  and  telephone  wires  of  the  same  poles 
with  lighting  and  power  wires,  the  distance  between 
the  two  inside  pins  of  each  cross  arm  should  not 
be  less  than  twenty-six  inches.  The  metallic 
sheaths  to  cables  should  be  thoroughly  and  per- 
manently connected  to  earth. 

Transformers  should  not  be  placed  inside  of 
any  building  excepting  central  stations  or  sub-sta- 
tions, and  should  not  be  attached  to  the  outside 
walls  of  buildings,  unless  separted  therefrom  by 

44 


substantial  supports  as  shown  on  page  49.  In  cases 
where  it  is  impossible  to  exclude  the  transformer 
and  primary  wiring  from  entering  the  building,  the 
transformer  should  be  located  as  near  as  possible 
to  the.  point  where  the  primary  wires  enter  the 
building,  and  should  be  placed  in  a  vault  or  room 
constructed  of  or  lined  with  fire-resisting  material, 
and  should  contain  nothing  but  the  transformers. 
It  is,  of  course,  the  safest  practice  to  place  all 
transformers  on  poles  away  from  the  building  that 
is  to  be  wired,  as  illustrated  on  page  49. 

Where  transformers  are  to  be  connected  to  high- 
voltage  circuits,  it  is  necessary  in  many  cases,  for 
best  ^protection  to  life  and  property,  that  the  sec- 
ondary system  be  permanently  grounded,  and  pro- 
vision should  be  made  for  it  when  the  transformers 
are  installed. 

Grounding  of  Low-Potential  Circuits.  The 
grounding  of  low-potential  circuits  is  only  recom- 
mended when  such  circuits  are  so  arranged  that 
under  normal  conditions  of  service  there  will  be 
no  appreciable  passage  of  current  over  the  ground 
wire. 

In  Direct-Current  3-Wire  Systems,  the  neutral 
wire  should  be  grounded,  and  when  grounded  the 
following  suggestions  should  be  complied  with: 

i— They  should  be  grounded  at  the  central  sta- 
tion on  a  metal  plate  buried  in  coke  beneath  per- 
manent moisture  level,  and  also  through  all  avail- 
able underground  water  and  gas  pipe  systems. 

2 — In  underground  systems  the  neutral  wire 
should  also  be  grounded  at  each  distributing  box 
through  the  box. 

45 


3 — In  overhead  systems  the  neutral  wire  should 
be  grounded  every  500  feet. 

,  In  Alternating-Current  Secondary  Systems. 
All  transformer  secondaries  of  distributing  sys- 
tems should  be  grounded,  and  the  following  sug- 
gestions should  be  complied  with: 

i— The  grounding  should  be  made  at  the  neutral 
point  or  wire,  whenever  a  neutral  point  or  wire 
is  accessible. 

2 — When  no  neutral  point  or  wire  is  accessible 
one  side  of  the  secondary  circuit  should  be  ground- 
ed. 

3 — The  ground  connection  should  be  at  the  trans- 
former or  on  thej  individual  service  and  when 
transformers  feed  systems  with  a  neutral  wire,  the 
neutral  wire  should  also  be  grounded  at  least  every 
500  feet. 

Inspection  Departments  having  jurisdiction  may 
require  grounding  if  they  deem  it  necessary. 

Ground  Connections.  When  the  ground  con- 
nections is  inside  of  any  building,  or  the  ground 
wire  is  inside  of,  or  attached  to  any  building  (ex- 
cept central  or  sub-stations)  the  ground  wire 
should  be  of  copper  and  have  an  approved  rubber 
insulating  covering. 

The  ground  wire  in  direct-current  3-wire  sys- 
tems should  not  at  central  stations  be  smaller  than 
the  neutral  wire  and  not  smaller  than  No.  6  B.  &  S. 
gage  elsewhere,  The  ground  wire  in  alternating- 
current  systems  should  never  be  less  than  No.  6 
B.  &  S.  gage. 

On    3-phase    systems,    the   ground    wire    should 

46 


have  a  carrying  capacity  equal  to  that  of  any  one 
of  the  three  mains. 

The  ground  wire  should,  except  for  central  sta- 
tions and  transformer  sub-stations,  be  kept  out- 
side of  buildings  as  far  as  practicable,  but  may  be 
directly  attached  to  the  building  or  pole  by  cleats 
or  porcelain  knobs.  Staples  should  never  be  used. 
The  wire  should  be  carried  in  as  nearly  a  straight 
line  as  practicable,  avoiding  kinks,  coils  and  sharp 
bends,  and  should  be  protected  when  exposed  to 
mechanical  injury. 

This  protection  can  be  secured  by  use  of  an  ap- 
proved molding,  and  as  a  rule  the  ground  wire  on 
the  outside  of  a  building  should  be  in  moulding  at 
all  places  where  it  is  in  within  seven  feet  from 
the  ground.  Conduit  may  be  used  for  this  purpose. 

The  ground  connections  for  central  stations, 
transformers,  sub-stations,  and  banks  of  transfor- 
mers should  be  made  through  metal  plates  buried 
in  coke  below  permanent  moisture  level,  and  con- 
nection should  also  be  made  to  all  available  under- 
ground piping  systems,  including  the  lead  sheath 
of  underground  cables. 

For  individual  transformers  and  building  ser- 
vices, the  ground  connection  may  be  made  to  water 
piping  systems  running  into  buildings.  This  con- 
nection may  be  made  by  carrying  the  ground  wire 
into  the  cellar  and  connecting  on  the  street  side  of 
meters,  main  cocks,  etc. 

Where  it  is  necessary  to  run  the  ground  wire 
through  any  part  of  a  building  it  should  be  pro- 
tected by  approved  porcelain  bushings  through  walls 
or  partitions  and  should  be  run  in  approved  mould- 


47 


Installation  of  Lightning  Arrester  on  outside  lines,  showing  method 
of  obtaining  a  good  "ground." 


ing,  or  conduit,  except  that  in  basements  it  may  be 
supported  on  porcelain. 

In  connecting  a  ground  wire  to  a  piping  system, 
the  wire  should  be  sweated  into  a  lug  attached  to 
an  approved  clamp,  and  the  clamp  firmly  bolted  to 


I 


Construction    Work — Installation    of   Transformers. 

the  water  pipe  after  all  rust  and  scale  have  been 
removed;  or  be  soldered  into  a  brass  plug  and  the 
plug  forcibly  screwed  into  a  pipe-fitting,  or,  where 
the  pipes  are  cast  iron,  into  a  hole  tapped  into  the 
pipe  itself.  For  large  stations,  where  connecting 
to  underground  pipes  with  bell  and  spigot  joints, 

49 


it  is  well  to  connect  to  several  lengths,  as  the  pipe 
joints  may  be  of  rather  high   resistance. 

Where  ground  plates  are  used,  a  No.  16  Stubbs' 
gage  copper  plate,  about  three  by  six  feet  in  size, 
with  about  two  feet  of  crushed  coke  or  charcoal, 
about  pea  size,  both  under  and  over  it,  would  make 
a  ground  of  sufficient  capacity  for  a  moderate-sized 
station,  and  would  probably  answer  for  the  ordinary 
sub-station  or  bank  of  transformers.  For  a  large 
central  station,  a  plate  with  considerably  more  area 
might  be  necessary,  depending  upon  the  other  un- 
derground connections  available.  The  ground  wire 
should  be  riveted  to  the  plate  in  a  number  of  places, 
and  soldered  for  its  whole  length.  Perhaps  even 
better  than  a  copper  plate  is  a  cast-iron  plate  with 
projecting  forks,  the  idea  of  the  fork  being  to  dis- 
tribute the  connection  to  the  ground  over  a  fairly 
broad  area,  and  to  give  a  large  surface  contact. 
The  ground  wire  can  probably  best  be  connected  to 
such  a  cast-iron  plate  by  soldering  it  into  brass 
plugs  screwed  into  holes  tapped  in  the  plate.  In 
all  cases,  the  joint  between  the  plate  and  the  ground 
wire  should  be  thoroughly  protected  against  cor- 
rosion by  painting  it  with  waterproof  paint  or 
some  equivalent. 

Ground  Detectors.  The  cuts  on  page  65  illus- 
trate a  few  practical  methods  of  detecting  grounds 
on  alternating  and  direct  current  circuits  which 
have  not  been  purposely  grounded,  as  described 
on  pages  45  and  46. 

In  using  any  one  of  these  methods  for  detecting 
grounds  always  see  that  the  circuit  TO  GROUND  is 

50 


left  open  after  testing  the  outside  circuits.  Some 
central  station  men  are  in  the  habit  of  leaving  the 
ground  circuit  closed  on  one  side  constantly  in  or- 
der that  any  ground  that  might  occur  on  the  other 
side  may  he  instantly  noticed.  This,  however,  is 
bad  practice,  as  it  greatly  reduces  the  insulation  of 
the  whole  system.  Test  all  circuits  once  a  day. 

MEASURING    RESISTANCE 

It  is  frequently  necessary  to  know  just  what  the 
insulation  resistance  of  a  line,  or  the  wiring  in  a 
building,  is  in  ohms. 


The   "Megger"    for   Measuring   Resistance. 

Heretofore  such  tests  have  been  made  with  some 
form  of  portable  testing  set  (Wheatstone  Bridge), 
or  by  the  voltmeter  method;  inconvenient  calcula- 
tions being  necessary  in  either  case. 

Now,  however,  there  is  on  the  market  a  new 
instrument,  called  the  Evershed  Megger,  by  means 
of  which  conductor  or  insulation  resistance  can 
be  measured  as  quickly  and  as  accurately  as  volt- 
si 


age  is  measured  with  a  voltmeter.  A  small  hand 
generator  is  mounted  in  the  case,  so  that  no  out- 
side source  of  current  is  required. 

Tests  by  the  "Megger-method"  are  made  as  fol- 
lows :  Connect  a  wire  from  one  side  of  the  circuit 
to  binding  post  of  the  Megger  marked  "Line,"  and 
with  another  piece  of  wire  connect  a  water  pipe  to 
the  "earth"-  binding  post  of  the  Megger.  Turn  the 
generator  handle  at  one  end  of  the  Megger  case, 
and  the  pointer  of  the  instrument  will  instantly 
show  the  correct  resistance — the  scale  being  grad- 
uated in  ohms. 

As  the  generator  voltage  is  usually  TOO  or  250 
volts,  there  is  the  added  advantage  that  tests  by  the 
"Megger-method"  are  practically  made  under 
working  conditions. 

Wiring  Table  No.  1.  For  Direct  Current  Work. 

Size  of  Wire,  Feet  per 

B.  &  S.  Gauge.  Volt-Ampere. 

0000 10068.4 

000  7998.7 

00  6389.5 

0 5025.1 

1  3974.5 

2  3166.5 

3 2495.0 

4  1980.0   , 

5  1347.0 

6  1248.7 

7    986.7 

8    779.6 

9    618.4 

10  495.0 

11  394.0 

12  312.3 

13 246.7 

14  194. 

52 


How  to  Use  the  Wiring  Table  No.  i.  The  col- 
umn entitled  size  of  wire  B.  &  S.  gage  gives  the 
various  sizes  used  in  wiring.  The  column  entitled 
feet  per  volt-ampere  gives  the  number  or  feet  that 
the  adjacent  size  of  wire  will  transmit  one  ampere 
with  a  lost  of  one  volt;  this  is  a  constant  quantity 
for  each  size  of  wire. 

The  distance  that  a  wire  will  transmit  a  given 
current  is  directly  proportional  to  the  volts  lost. 

The  distance  that  a  wire  will  transmit  a  cur- 
rent with  a  certain  volt  loss  is  inversely  propor- 
tional to  the  current. 

If,  therefore,  it  is  desired  to  know  how  far  a 
given  wire  will  transmit  a  given  current  at  a  cer- 
tain given  line  loss,  select  from  the  second  column 
opposite  the  £ize  of  the  wire  constant  in  the  feet? 
per-volt-ampere  column  and  multiply  this  figure 
by  the  desired  loss  and  divide  by  the  current  to 
be  transmitted. 

If  it  is  desired  to  know  how  much  current  can 
be  transmitted  a  given  distance  with  a  certain  line 
loss  multiply  this  constant  by  the  line  loss  and 
divide  by  the  distance. 

If  it  is  desired  to  know  what  line  loss  will  oc- 
cur when  transmitting  a  certain  current  through 
a  certain  size  of  wire  multiply  the  distance  and 
current  together  and  divide  by  fhe  constant  for 
the  size  of  wire  which  it  is  desired  to  use. 

Take  a  Practical  Example.  Let  it  be  asked, 
"How  far  will  a  No.  6  wife  transmit  20  amperes 
with  a  line  loss  of  15  volts?"  The  constant  for 
No.  6  wire  is  1248.7;  multiply  this  by  the  line  loss 

53 


of  15  volts  and  we  have  18730.5,  and  dividing  this 
by  the  current,  20  amperes,  we  have  936.5.  Con- 
versely, suppose  we  have  a  distance  of  936.5  feet 
and  must  transmit  over  it  20  amperes,  how  much 
line  loss  will  obtain  ?  Multiply  this  distance  of 
936.5  by  the  current  to  be  transmitted,  and  we 
obtain  18/30,  dividing  this  by  the  constant  for  No. 
6  wire,  1248.7,  we  obtain  14.999  v°lts  lme  l°ss>  or 
practically  15  volts. 

Similarly :  Suppose  we  have,  a  distance  of  936.5 
feet,  and  the  conditions  are  such  that  at  most  it 
must  not  exceed  a  line  loss  of  more  than  15  volts. 
How  many  amperes  can  we  transmit  with  a  No.  6 
wire  ? 

To  do  this  we  multiply  the  constant  of  No.  6 
wire,  1248.7  by  the  line  loss  of  15  volts,  obtaining 
.18730.5,  and  dividing  this  by  the  distance,  963.5 
feet,  we  obtain  20.0005,  or  practically  20  amperes. 

Finally,  and  as  is  more  often  the  case,  the  dis- 
tance and  line  loss  and  current  are  given  ;  we  have 
to  multiply  the  distance  by  the  current  and  divide 
.  by  the  line  loss  which  will  give  us  the  constant  of 
the  wire  to  use.  In  the  preceding  case  of  936.5 
feet,  we  multiply  by  the  current  of  20  amperes  and 
obtain  18730.;  dividing  this  by  the  line  loss  of  15 
volts  we  obtain  12486.6,  which  is  practically  12,- 
487,  the  constant  for  No.  6  wire. 

If  this  constant  had  been  larger  still,  but  not 
so  large  as  the  constant  for  No.  5  wire,  it  would 
be  proper  to  select  the  nearest  constant. 

Wires  for  Outside  Use  have  in  most  cases  a 
" weather-proof"  (see  page  67)  insulation,  except 
service  wires,  which  should  be  "rubber  covered" 

54 


see  page  66).  Any  insulating  covering  for  wires 
exposed  to  the  weather  on  poles  is  in  time  ren- 
dered useless.  The  real  insulation  of  the  system 
is  dependent  upon  the  porcelain  or  glass  insulat- 
ors on  which  the  wires  are  supported. 

Constant-Potential  Currents  of  over  5,000  volts 
should  be  given  special  care  and  attention  as  to 
their  installation  and  location  with  respect  to  ad- 
joining or  near-by  property  or  other  outside  wiring. 

Accidental  crosses  between  such  lines  and  low- 
potential  lines  may  allow  the  high-voltage  current 
to  enter  buildings  over  a  large  section 'of  adjoining 
country.  Moreover,  such  high-voltage  lines,  if 
carried  close  to  buildings,  hamper  the  work  of  fire- 
men in  case  of  fire  in  the  building. 

It  is  fully  understood  that  it  is  impossible  to 
frame  rules  which  will  cover  all  conceivable  cases 
that  may  arise  in  construction  work  of  such  an  ex- 
tended and  varied  nature. 

Every  reasonable  precaution,  however,  should  be 
taken  in  arranging  routes  so  as  to  avoid  exposure  to 
contacts  with  other  electric  circuits.  On  exist- 
ing lines,  where  there  is  a  liability  to  contact,  the 
route  should  be  changed  by  mutual  agreement  be- 
tween the  parties  in  interest  wherever  possible. 

Such  lines  should  not  approach  other  pole  lines 
nearer  than  a  distance  equal  to  the'  height  of  the 
taller  pole  line,  and  such  lines  "hpuld  not  be  on 
the  same  poles  with  other  wires,  except  that  signal- 
ing wires  used  by  the  company  operating  the  high- 
pressure  system,  and  which  do  not  enter  property 
other  than  that  owned  or  occupied  by  such  com- 
pany may  be  carried  over  the  same  poles. 


Where  such  lines  must  necessarily  be  carried 
near  other  pole  lines,  or  where  they  should  neces- 
sarily be  carried  on  the  same  poles  with  other  wires, 
extra  precautions  to  reduce  the  liability  of  a  break- 
down to  a  minimum  should  be  taken,  such  as  the 
use  of  wires  of  ample  mechanical  strength,  widely 
spaced  cross  arms,  short  spans,  double  or  extra 
heavy  cross  arms,  extra  heavy  pins,  insulators,  and 
poles  thoroughly  supported.  If  carried  on  the 
same  pole  with  other  wires,  the  high-pressure  wires 
should  be  carried  at  least  three  feet  above  the  other 
wires. 

Where  such  lines  cross  other  lines,  the  poles  of 
both  lines  should  be  of  heavy  and  substantial  con- 
struction. 

Whenever  it  is  feasible,  end  insulator  guards 
should  be  placed  on  the  cross  arms  of  the  upper 
line.  If  the  high-pressure  wires  cross  below  the 
other  lines,  the  wires  of  the  upper  line  should  be 
dead-ended  at  each  end  of  the  span  to  double- 
grooved,  or  to  standard  transposition  insulators, 
and  the  line  completed  by  loops. 

When  it  is  necessary  to  carry  such  high-voltage 
lines  near  buildings,  they  should  be  at  such  height 
and  distance  from  the  building  as  not  to  interfere 
with  firemen  in  event  of  fire;  therefore,  if  within 
25  feet  of  a  building,  they  should  be  carried  at  a 
height  not  less  than  that  of  the  front  cornice,  and 
the  height  should  be  greater  than  that  of  the  cor- 
nice, as  the  wires  come  nearer  to  the  building. 

It  is  evident  that  where  the  roof  of  the  building 
continues  nearly  in  line  with  the  walls,  as  in  Man- 
sard roofs,  the  height  and  distance  of  the  line 

56 


should  be   reckoned   from   some  part  of   the   roof 
instead   of   from  the  cornice. 

POLES   FOR   LIGHT  AND   POWER 
WIRES 

It  is  very  essential. to  a  proper  installation  that 
the  poles  receive  due  consideration,  a  fact  that  is 
too  often  overlooked. 

In  selecting  the  style  of  pole  necessary  for  a  cer- 
tain class  of  work,  the  conditions  and  circumstances 
should  be  considered.  They  may  be  arranged  in 
three  classes,  the  size  of  wire  they  are  to  carry 
being  one  of  the  important  regulating  circum- 
stances. 

First  Class.  Alternating-current  plants  for 
lighting  small  towns.  Main  line  of  poles  should 
consist  of  poles  of  from  30  to  35  feet  with  6-inch 
tops.  These  are  strong  enough  for  all  the  weight 
that  is  placed  upon  them.  No  pole  less  than  30 
feet  with  6-inch  top  should  be  placed  on  a  corner 
for  lamps.  The  height  of  trees,  of  course,  will 
have  to  be  considered  in  many  cases.  For  the  Edi- 
son municipal  system,  where  more  than  one  set 
of  wires  are  used  for  street  lighting,  a  6-inch  top 
should  be  the  size  of  the  poles,  the  length  being 
not  less  than  30  feet,  and  more  if  the  streets  be 
hilly  and  filled  with  trees. 

Second  Class.  Town  lighting  by  arc  lights. 
All  poles  should  be  at  least  6-inch  tops.  The  cor- 
ner poles  should  be  6^2 -inch  tops,  and  wherever 
the  cross  arms  are  placed  on  a  pole  at  different 
angles,  the  pole  should  be  at  least  a  6^/2 -inch  top. 
A  3O-foot  pole  is  sufficiently  large  for  the  main 

57 


line,  but  it  would  be  advisable  to  place  35-foot  poles 
on  corners. 

Third  Class.     Where  heavy  wire,  such  as  No. 
oo,  is  used  for  feeder  wire,  the  poles  should  be  at 
least  7-inch  tops.     Where  mains   are   run  on   the 
same   pole   line   the    strain   is   somewhat   lessened, 
and  poles  of  smaller  size  will  answer  all  purposes. 
Cull  Poles.     The  question  as  to  what  is  a  cull 
pole  is  something  on  which  many  authorities  dif- 
fer.    Of  course,  if  specifications  call  for  a  certain- 
sized  pole,  parties   supplying  the  'poles   should  be 
compelled  to  send  the  sizes  called  for.     All  poles 
that  are  smaller  at  the  top  than  the  sizes  agreed 
upon,  are  troubled  with  dry  rot,  large  knots  and 
bumps,  have  more  than  one  bend,  or  have  a  sweep 
of  over  twelve  inches,  should  certainly  be  classed 
as  cull  poles.     Specifications  for  electric  light  and 
power  work  should  be,  and  in  many  cases  are,  much 
more  severe  than  those  required  by  telegraph  lines. 
A  cull  pole,  one  of  good  material,  is  the  best  thing 
for  a  guy  stub,  and  is  frequently  used  for  this  pur- 
pose.    A  cedar  pole  is  always  preferable  to  any 
other,   owing  to  the   fact  that  it  is  very  light  in 
comparison  to  other  timber,  and  is  strong,  durable, 
and  very  long  lived. 

Pole  Setting.  In  erecting  poles,  it  seems  to  be 
the  universal  opinion  of  the  best  posted  construc- 
tion men  that  a  pole  should  be  set  at  least  five  feet 
in  the  ground,  and  six  inches  additional  for  every 
five  feet  additional  length  above  thirty-five  feet. 
Also  additional  depths  on  corners.  Wherever 
there  is  much  moisture  in  the  ground,  it  is  of  much 
value  to  pain  or  smear  the  butt  ends  of  the  pole 

58 


with  pitch  or  tar,  allowing  this  to  extend  about  two 
feet  above  the  level  of  the  ground.  This  protects 
the  pole  from  rot  at  the  base.  The  weakest  part 
of  the  pole  is  just  where  it  enters  the  ground. 
Never  set  poles  further  than  125  feet  apart;  spac- 
ing not  over  no  feet  is  good  practice. 

Pole  Holes  should  be  dug  large  enough  so  that 
the  butt  of  the  pole  can  be  dropped  straight  in 
without  any  forcing,  and  when  the  pole  is  in  posi- 
tion only  one  shovel  should  be  used,  to  fill  in,  the 
earth  being  thoroughly  tamped  clown  with  iron 
tampers  at  every  step  until  the  hole  is  completely 
filled  with  solidly  packed  earth.  Where  the  ground 
is  too  soft  for  proper  tamping,  a  grouting  com- 
posed of  one  part  of  Portland  cement  to  two  parts 
of  sand  mixed  with  broken  stone  may  be  used  to 
make  an  artificial  foundation. 

Painting.  When  poles  are  to  be  painted,  a 
dark  olive  green  color  should  be  chosen,  in  order 
that  they  may  be  as  inconspicuous  as  possible.  One 
coat  of  paint  should  be  applied  before  pole  is  set, 
and  one  after  pole  is  set.  Tops  should  be  pointed 
to  shed  water. 

All  poles  35  feet  long  and  over  are  usually  loaded 
on  two  cars. 

For  chestnut  poles  add  50  per  cent,  to  weights 
as  given  above. 

Cross  Arms.  The  distance  from  the  top  of  the 
pole  to  the  cross  arm  should  be  equal  to  the  diam- 
eter of  pole  at  the  top.  All  cross  arms  should  be 
well  painted  with  one  coat  of  paint  before  plac- 
ing, and  must  be  of  standard  size. 

Cross    arms    of    four   or   more    pins    should   be 

59 


braced,  using  one  or  two  braces  as  occasion  de- 
mands. Cross  arms  on  one  pole  should  face  those 
on  the  next,  thereby  making  the  cross  arms  on 
every  other  pole  face  in  one  direction.  All  wooden 
pins  should  have  their  shanks  dipped  in  paint  and 
should  be  driven  into  the  cross  arm  while  the  paint 
is  wet.  The  upper  part  of  the  pin  should  also  be 
painted.  Iron  pins  can  be  furnished  for  corners 
where  there  is  a  heavy  strain,  but  are  not  advised, 
it  being  preferable  to  use  the  construction  as  shown 
in  the  diagrams.  Put  double  arms  on  the  pole 
where  feeder  wires  end.  (See  p.  64.) 

Guard  Irons.  Guard  irons  should  be  placed  at 
all  angles  in  lines  and  on  break  arms.  (See  p.  64.) 

Steps.  All  junction  and  lamp  poles  should  be 
stepped  so  that  the  distance  between  steps  on  the 
same  side  of  the  pole  will  not  be  over  36  inches. 
Poles  carrying  converters  should  also  be  stepped. 

Guys.  All  poles  at  angles  in  the  line  should 
be  properly  guyed,  using  No.  4  B.  &  S.  galvanized 
iron  wire,  or  two  No.  8  wires  twisted.  All  junction 
poles  should  also  be  guyed.  Never  attach  a  guy 
wire  to  a  pole  so  that  it  prevents  a  cross  arm  from 
being  removed. 

For  alternating  current  work,  double  or  triple 
petticoat  insulators  are  recommended.  (See  cuts 
on  page  41.) 

Primary  Wires  on  Poles.  When  running  more 
than  one  alternating  current,  single-phase  primary 
circuit  upon  the  same  line  of  poles  the  wires  of  each 
circuit  should  be  run  parallel  and  on  adjacent  pins, 
as  shown  below,  so  as  to  avoid  any  fluctuation  in 
the  lamps  due  to  induction.  The  lines  lettered  A 

60 


and  A  are  for  circuit  No.  i,  and  B  and  B  for  cir- 
cuit No.  2,  etc.' 

A 


A 


B 


B 


Underground  Conductors  should  be  protected 
against  moisture  and  mechanical  injury  where 
brought  into  a  building,  and  all  combustible  material 
should  be  kept  from  the  immediate  vicinity. 

They  should  not  be  so  arranged  as  to  shunt  the 
current  through  a  building  around  any  catch-box. 

Where  underground  service  enters  building 
through  tubes,  the  tubes  shall  be  tightly  closed  at 
outlets  with  asphaltum  or  other  non-conductor,  to 
prevent  gases  from  entering  the  building  through 
such  channels. 

CEDAR   POLES    FOR    ELECTRIC   LIGHT   WORK. 


SIZE. 

Average 
weight, 
pounds 
each. 

No.  of 
Poles 
to  a  Car 

SIZE. 

Average 
weight, 
pounds 
each. 

No.  of 
Poles 
tn  a  Car 

25-  ft.,  5-inch  top 

200 

150 

35-ft.,   7-inch   lop 

650 

90 

25   "      5^  "     " 

225 

130 

40  "      6      "     " 

800 

80 

25  "      6      !'     " 

250 

100 

40  "      7      "     " 

900 

75 

28  "      7      "     " 

400 

80 

45   "      6       "     " 

900 

70 

30  "      5       "     " 

300 

110 

45  "      7      "     " 

1000 

65 

30  "      6      "     " 

350 

90 

60  "      6      "     " 

1200 

55 

30  "      7       "•    " 

420 

75 

65  "      6      "     " 

1400 

45 

35  "     6      "     " 

550 

100 

61 


POLE  LINE  DATA 


Gauge  No.  B.  &  i 

Diam.  Bare  wire,  i 
Ohms  Res.  B.  wire 
Wt.  (lbs.)perl,00( 
Wt.      "       u     Mile 

Poles  per  Mile 

4-0 

.460 
.2622 
775 
4092 

3-0 

.40964 
.33 
630 
3326 

2-0 

.3648 
.4164 
490 

2587 

1-0 

.3249 
.5252 
400 
2112 

1 

.2893 
.6642 
306 
1616 

2 

.2576 
.8337 
268 
1415 

n  Thousandths 
at  75°  per  mile 
)  ft.  Triple  B  .  . 

Dist.  bet. 
Poles—  Ft. 

Approximate  Wt.  of  Weatherproof 
Wire  between  Poles         i 

20                       ... 

264.00 
251.40 
240.10 
229.56 
220.00 
211.20 
203.07 
195.55 
188-55 
182.09 
176.00 
170.30 
165.00 
160.00 
155.29 
150.85 
146.66 
142.70 
138.96 
135.38 
132.00 
128.78 
125.71 
122.79 
120.00 
117-33 
114.78 
112.34 
110.00 
107.75 
105.60 
103.52 
101.53 
99.64 
97.77 
96.00 

210-73 
200.66 
191.64 
183.24 
175-60 
168.59 
162.07 
156.10 
150-46 
145.34 
140.50 
135.92 
131.71 
127.72 
123-96 
120-38 
117-07 
113.90 
110.93 
108-05 
105.37 
102-79 
100.35 
98-01 
95-79 
93-66 
91-61 
89-67 
87-80 
86.01 
84.30 
82-63 
81.04 
79.54 
78-04 
76-63 

171.31 
163.14 
155.81 
148.96 
142.76 
137-04 
131.76 
126.90 
122.35 
118.16 
114.21 
110-51 
107.07 
103-82 
100-76 
97-89 
95-15 
92.60 
90.17 
87-84 
85.65 
83  56 
81.58 
79.68 
77-87 
76-15 
74.48 
72.89 
71.38 
69-92 
68.53 
67-18 
65.89 
64.65 
63.44 
65-29 

133.24 
126-87 
121.17 
115.85 
111.03 
106.58 
102.48 
98.69 
95.16 
91.89 
88.83 
85.95 
83.28 
80-75 
78-37 
76.14 
74.02 
72.02 
70.13 
68-33 
66-62 
64.99 
63.44 
61-97 
60.56 
59.21 
57-93 
56-70 
55.52 
54.38 
53  29 
52.24 
51.24 
50.29 
49.34 
48-45 

108-78 
103-58 
98.91 
94.57 
90-64 
87-01 
83.65 
80.56 
77-68 
75.01 
72.51 
70-16 
67.98 
65.92 
63-98 
62-15 
60.43 
58-79 
57-25 
55.77 
54-38 
53.05 
51.79 
50-59 
49.47 
48.38 
47  27 
46  28 
45.32 
44.39 
43.50 
42-65 
41-83 
41.05 
40.28 
39-55 

83-21 
77.24 
75-67 
72.36 
69.34 
66.56 
64.00 
61-64 
59.43 
57.39 
55.47 
53.67 
52.01 
50.43 
48.94 
47.55 
46-23 
44.98 
43.88 
42-67 
41  61 
40.59 
39.62 
38-70 
37-82 
36.98 
36.18 
35.40 
34.67 
33*96 
33.28 
32.63 
32.00 
31.40 
30.82 
30-25 

72.87 
69.39 
66.27 
63.36 
60.72 
58.29 
56.05 
53.97 
52.05 
50.26 
48.58 
47.00 
45.55 
44.16 
42.86 
41.64 
40.48 
39.39 
38-36 
37-37 
36.43 
35-54 
34.70 
33-89 
33-12 
32.38 
31.68 
31  01 
30.36 
29.74 
29-15 
28-57 
28.02 
27-50 
26.98 
^6-50 

21     

22 

23       

24 

25        

26 

27  

28-..    

Oq 

30 

31.  

32        .  .         

33  

34          

OC 

3g     

07 

3g           

39 

40  ...             ..... 

41 

42        

43  

44              

45 

46              

47 

4g            

49                  .... 

50  ..  . 

51              

CO 

53              ... 

c4 

55        

62 


POLE  LINE  DATA.— Continued. 


Gauge  No.  B.  &  S. 

Diam.  Bare  Wire, 
Res.  B.  Wire,  per 
Wt.  1,000  ft.  Tripl 
\Vr.  Mile 

No.   3 

.2294 
1.058 
210 
1109 

App 

No.   4 

.2043 
1.333 
164 
866 

roxima 
Wii 

No.  '5 

.1819 
1.6748 
145 
766 

te  Wt. 
•e  betw 

No.  6. 

.1620 
2.114 
112 
591 

of  We 
een  PC 

No.   7 

.1442 
2.673 

atherpr 
)les 

No.   8 

.1285 
3.387 
78 
412 

oof 

Thousandths...  . 
mile  at  75°  
e  Braid  

Poles  Per 
Mile 

Distance 
Between  Poles 
—  Feet 

20  

264.00 
251.40 
240.10 
229-56 
220.00 
211.20 
203.07 
195-55 
188-55 
182.09 
176.00 
170.30 
165.00 
160.00 
155.29 
150.85 
146.66 
142.70 
138.96 
135.38 
132.00 
128.78 
125-71 
122.79 
120.00 
117-33 
114.78 
112.34 
110.00 
107-75 
105.60 
103-52 
101.53 
99.64           ? 
97.77 
98  00 

57.10 
54.38 
51.93 
49.65 
47.59 
45.68 
43.92 
42-29 
40.78 
39.39 
38.07 
36.83 
35.69 
34.61 
33-59 
32.63 
31.72 
30-87 
30-06 
29.28 
28.55 
27-85 
27.19 
26.56 
25.96 
25.38 
24.83 
24-30 
23-79 
23.31 
22-84 
22.39 
21.96 
•21.55 
21.15 
20-76 

44.59 
42.46 
40.55 
38.77 
37.16 
35.68 
34.30 
33.03 
31.85 
30-76 
29.73 
28.77 
27.87 
27.03 
26.23 
25.48 
24.78 
24.10 
23.47 
22.86 
22.30 
21.75 
21.24 
20.74 
20.27 
19.82 
19.39 
18.98 
18.58 
18.20 
17.84 
17.49 
17.15 
16-83 
16.51 
16.21 

39.43 
37.54 
35.86 
34.28 
32.86 
31.54 
30.33 
29.21 
28.16 
27.19 
26.29 
25.43 
24.64 
23.90 
23.19 
22.53 
21.90 
21.31 
20.76 
20.22 
19-71 
19-23 
18-78 
18.34 
17.92 
17.52 
17-14 
16-78 
16.43 
16.09 
15.77 
15.46 
.5.16 
14.88 
14.60 
1434 

30.45 
29.00 
27.70 
26.48 
25.38 
24.36 
23-42 
22-56 
21.75 
21.00 
20-30 
19.64 
19.03 
18.46 
17.91 
17.40 
16.92 
16.46 
16-03 
15.62 
15.23 
14.85 
14.50 
14.17 
13.84 
13.53 
13.24 
12-96 
12,69 
12-43 
12.18 
11.95 
11.71 
11.49 
11.28 
11.07 

.':;:. 

21.21 
20.20 
18.29 
18.44 
17.67 
16.97 
16.32 
15.71 
15-15 
14.63 
14.14 
13-68 
13.26 
12.85 
12.47 
12.12 
11.78 
11.46 
11.16 
10.88 
10.61 
10-34 
10.10 
9.86 
9.64 
9.43 
9,22 
9.02 
8-84 
8.66 
8.48 
8-32 
8-16 
8.00 
7.85 
7.71 

21 

22  

23  
24        

25 

26  

27 

28  

29 

30  

31  .... 

32  

33 

34  

35  

36  

37  .... 

38  

39  

40 

41  

42  

43 

44  

45 

46  

47  

48  

49  

50 

51  

52  

53     ... 

54  
55          

G3 


ANGLES  OF  BRACES 
WILL  BE  GOVERNED 
BY  CIRCUMSTANCES 


BLOCK  *vu. 


X  VARIES  AS 
THE  DIAMETER 
OF  THE  POLE 


CONSTRUCTION  WORK 
Position  of  Cross-Arms  when  Turning  Corners 

When  running  a  heavy  line  where  it  is  necessary  to  use  two  cross 
arms  fastened  as  shown  in  Fig.  2.    If  lines  are  not  heavy,  only  one 
cross  arm  will  be  necessary.    In  case  lines  cross  the  street  diag- 
onally, the  arms  where  the  wires  leave  and  those  to  which  they 
run  are  both  set  at  an  angle.    When  turning  an  abrupt  cor- 
ner, only  one  arm  is  turned.    The  above  cannot  be  used 
where  feeders  tap  into  double  branches.     In  such  cases 
the  method  as  given  in  Fig.  1  is  used. 

64 


CONNECTIONS 

OF 

GROUND  DETECTORS    , 


ALTERNATING 

GROUND  DETECTOR 

FOR  ONE  CIRCUIT 


ALTERNATING 
GROUND  DETECTOR 
FOR  TWO  CIRCUITS 


DIRECT  CURRENT 
GROUND  DETECTOR 


NEUTRAL  WIRE  IN 
3-WIRE  SYSTEM 


TO  GROUND 

IF  THE  LAMP  BURNS  A  GROUND  IS  INDICATED 
ON  THE  OPPOSITE  SIDE  OF  THE  CIRCUIT 
FROM  THAT  TO  WHICH  THE  SWITCH 
IS  CONNECTED 


INSIDE  WIRING 

General  rules  for  all  systems  and  voltages  for 
light,  power  and  heat,  when  protected  by  service 
cut-out  and  switch. 

Approved  "Rubber-Covered  Wire"  should  be 
used  exclusively  in  all  interior  wiring.  Although 
the  Fire  Underwriters  allow  "Slow  Burning"  wire 
to  be  used  in  dry  places  when  wiring  is  entirely 
exposed  to  view  and  rigidly  supported  on  porce- 
lain or  glass  insulators. 

The  copper  conductors  before  being  rubber  cov- 
ered should  be  thoroughly  tinned  and  the  thickness 
of  the  rubber  covering  should  correspond  to  the 
following  table  for  voltages  up  to  600: 

From  No.  14  to  No.  8  inclusive  ,\  in 

"  6  to     "  a  I's  in 

i  to     '  oooo  6\  in 

Over     oooo     to  '  500000  c.  m.  33,  in 

500000  c.  m.  to  "  i oooooo  *  &  in 

Larger  than  "  i  oooooo  "  I  in 

For  voltages  above  600  the  rubber  covering  is 
correspondingly  thicker.  Consult  your  supply 
dealer  or  any  of  the  following  manufacturers  who 
will  furnish  the  proper  insulation  for  the  voltage 
required. 

Complete  list  of  Manufacturers  of  Approved 
"Rubber  Covered"  Wires : 

A.   A.    Wire   Co.,    Inc Newark,    N.    J. 

American    Electrical    Works Providence,    R.    I. 

American    Steel    &    Wire    Co Worcester,    Mass. 

Atlantic    Insulated    Wire    &    Cable    Co New    York. 

Bay  State  Insulated  Wire  &  Cable  Co Hyde  Park,  Mass. 

Belden    Mfg.    Co Chicago,    111. 

Bishop   Gutta  Percha   Co New   York. 

Boston   Insulated   Wire   &   Cable   Co Boston. 

Bourn  Rubber  Co Providence,  R.   I. 

Collyer   Insulated   Wire    Co Pawtucket,   R.   I. 

Crescent  Insulated  V/ire  &  Cable  Co Trenton,   N.  J. 

Detroit   Insulated   Wire    Co , Detroit,    Mich. 

66 


Klectric    Cable    Co Bridgeport,    Conn. 

General    Electric    Co Schenectady,    N.     Y. 

Goodrich    Co.,    B.    F Akron,    Ohio. 

Goodyear   Rubber    Insulating   Co New    York. 

Habirshaw    Wire    Co Yonkers,    N.    Y. 

Hazard    Mfg.    Co Wilkes-Barre,    Pa. 

Indiana    Rubber    &    Insulated    Wire    Co". Jonesboro,    Ind. 

Kerite    Insulated   Wire    &   Cable   Co New   York. 

Lowell    Insulated    Wire    Co Lowell,    Mass. 

Marion   Insulated    Wire    Co Marion,    Ind. 

National   India  Rubber  Co New  York. 

New    York    Insulated    Wire    Co New  York. 

The    Okonite    Co New  York. 

Phillips    Insulated    Wire    Co Pawtucket,    R.    I. 

Roebling's    Sons    Co.,    John    A t Trenton,    N.    J. 

Rome    Wire   Co Rome,   N.    Y. 

Safety    Insulated    Wire    &    Cable    Co New    York. 

Simplex  Wire   &   Cable    Co Boston. 

Standard    Underground    Cable    Co Pittsburg. 

\Vaterbury    Company New    York. 

Chicago    Insulated    Wire    &    Mfg.    Co Chicago. 

(Slow-Burning    and    Weatherproof.) 


"Slow-Burning"  Wire  should  have  an  insula- 
tion consisting  of  three  braids  of  cotton  or  other 
thread  with  the  interstices  well  filled  with  a  fire- 
proofing  compound.  The  outer  braid  should  be 
designed  to  resist  abrasion  and  have  its  surface 
finished  smooth  and  hard. 

The  complete  covering  should  be  of  a  thickness 
not  less  than  that  given  in  the  following  table: 

Form  No.     14  to  No.  8     inclusive,  3/64  inch 

7  to  '  2        "    1/16  " 

1  to  '  0000        "    5/64  " 

250000  to  '  500000  c.  m.    "    3/32  " 

500000  to  '  1000000  c.  m.    "    7/64  " 

Larger  than  1000000  c.  m.    "    1/8   " 

"Weatherproof"  Wire  is  for  out-door  use,  and 
should  have  a  covering  of  at  least  three  braids 
thoroughly  impregnated  with  a  dense  moisture  re- 
pellent which  should  stand  a  temperature  of  160° 
Fahrenheit  without  dripping.  The  thickness  should 
correspond  to  that  of  "Slow  Burning"  wire,  and 

67 


the  outer  surface  should  be  thoroughly  slicked 
down. 

Carrying  Capacity  of  Wires.  The  table  on 
page  8 1  gives  the  safe  carrying  capacity  of  wires 
from  No.  18  B.  &  S.  to  cables  of  2,000,000  circu- 
lar mils.  No  wires  smaller  than  No.  14  should  be 
used  except  for  fixture  wiring  and  pendant  cords. 
For  fixtures  as  small  as  No.  18  may  be  used.  (Sec 
page  99.) 

Tie  Wires  should  have  an  insulation  equal  to 
that  of  the  conductors  they  confine. 

All  wires  of  the  size  of  No.  8  B.  &  S.  gage  or 
larger  when  used  in  connection  with  knobs  should 
be  securely  tied  thereto  with  tie  wires  having  equal 
insulation. 

Solid  porcelain  knobs  should  be  used  at  the  end 
of  runs  where  circuits  are  terminated.  Split 
knobs  or  cleats  should  be  used  for  conductors  small- 
er than  No.  8  B.  &  S.  gage,  except  at  the  end  of 
runs: 

All  knobs  or  cleats  should  be  fastened  by  screws 
of  generous  length  and  should  have  washers  under 
their  heads  to  prevent  the  screw  from  cracking  the 
porcelain. 

Splicing  should  be  done  so  as  to  make  the 
wires  mechanically  and  electrically  secure  without 
solder;  then  they  should  be  soldered  to  insure  pre- 
servation from  corrosion  and  consequent  heating 
from  poor  contact.  Then  thoroughly  taped. 

All  joints  should  be  soldered  unless  made  with 
some  form  of  approved  splicing  device  such  as  Dos- 
sert  joints.  (See  page  40.)  This  ruling  applies  to 
joints  and  splices  in  all  classes  of  wiring. 

68 


Stranded  Wires,  except  flexible  cords,  should 
have  their  tips  soldered  before  being  fastened  under 
clamps  or  binding  screws.  Both  solid  and  stranded 
wires  having  a  conductivity  greater  than  No.  8  B. 
£  S.  gage  should  be  soldered  into  lugs  for  all  ter- 
minal connection  unless  Dossert  lugs  are  used. 

Wiring  Table,  No.  2  (See  page  70.)  The  fol- 
lowing examples  show  the  method  of  using  the  table 
on  the  following  page. 

1.  What  size  of  wire  should  we  use  to  run  50 
5O-watt  carbon  lamps,  of  no  volts,  a  distance  of 
150  feet  to  the  center  of  distribution  with  the  loss 
of  2  volts?    First  multiply  the  amperes,  which  will 
be  22.75   (5°-5°  watt  no-v.  lamps  take  22.75  am- 
peres,  see  table  on  page  115),  by  the  distance,  150 
feet,    which   will   equal   3,412   ampere   feet.    Then 
refer  to  the  columns  headed  "Actual  Volts  Lost/' 
and  as  we  are  to  have  only  a  loss  of  two  volts  look 
down  the  column  headed  2  until  you  come  to  the 
nearest  corresponding  number  to  3,412  and  we  find 
that  3,900  is  the  best  number  to  use.    Put  your  pen- 
cil on  the  number  3,900  and  follow  that  horizontal 
column  to  the  left  until  you  come'  to  the  vertical 

vcolumn  headed  "Size  B.  &  S."  and  you  find  that  a 
No.  4  B.  &  S.  wire  will  be  the  proper  size  to  use  in 
this  case. 

2.  What  size  wire  should  we  use  to  carry  cur- 
rent for  a  motor  that  requires  30  amperes  and  220 
volts,  and  is  situated  200  feet  from  the  distributing 
pole,  the  "drop"  in  volts  not  to  exceed  2  per  cent.? 
First  multiply  30  amperes  by  200  feet,  as  we  did  in 
the  first  example,  and  we  get  .6,000  ampere  feet. 
Now  look  at  the  upper  left  hand  corner  of  the  table 

69 


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70 


and  you  will  see  a  vertical  column  headed  "Volts." 
Go  down  this  column  until  you  come  to  220  and 
follow  the  horizontal  column  to  the  right  until  you 
come  to  the  figure  1.8  which  is  the  nearest  we  can 
come  to  a  2  per  cent,  loss  without  a  greater  loss  or 
"drop."  Place  your  pencil  on  a  figure  1.8  and  fol- 
low down  the  vertical  column  of  figures  until  you 
come  to  the  nearest  corresponding  figure  to  6,000, 
which  we  find  to  be  6,200.  Then  with  your  pencil 
on  this  figure  follow  the  horizontal  column  to  the 
left  and  we  find  that  a  No.  5  B.  &  S.  wire  is  a  prop- 
er size  to  use  for  the  above  conditions. 

3.  Supposing  we  have  occasion  to  inspect  a  piece 
of  wiring,  and  find  a  dynamo  operating  50-50  watt 
no-volt  lamps  at  a  distance  of  150  feet,  and  our 
wire  gauge  shows  that  wire  in  use  is  a  No.  12  B. 
&  S.,  at  what  loss,  or  "drop,"  are  these  lamps  be- 
ing operated  ?  First  multiply  the  amperes,  which 
will  be  22.75  (5°~5°  watt  no-volt  lampfs  take  22.75 
amperes  (see  table  on  page  115),  by  the  distance, 
150  feet  and  we  get  3,412  ampere  feet.  As  we  find 
in  use  a  No.  12  B.  &  S.  wire  we  look  for  the  verti- 
cal column  headed  "Size  B.  &  S."  and  follow  it 
down  until  we  come  to  12.  With  our  pencil  on  the 
figure  12  we  travel  along  the  horizontal  line  to  the 
right  until  we  come  to  the  nearest  corresponding 
number  to  3,412,  which  we  find  to  be  3,050.  Then 
starting  at  this  number  we  travel  up  the  vertical 
column  and  we  find  a  loss  of  about  10  actual  volts, 
or  at  an  8  per  cent,  loss,  which  would  greatly  re- 
duce the  candle-power  or  brilliancy  of  his  lamps.  A 
larger  wire  should,  therefore,  be  used. 

71 


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72 


Wiring  Calculations  for  Alternating  Current. 

When  figuring  wire  sizes  for  Alternating  Current, 
except  in  cases  of  long  distances,  the  following 
methods  of  calculating  should  be  used. 

As  compared  with  the  circular  mileage  of  each 
conductor  of  a  two  wire  system,  that  of  each  con- 
ductor of  other  systems,  transmitting  same  power 
with  the  same  distance,  volts  lost,  and  lamp  voltage 
is,  for: — 

3  wire,  single  phase 25.0% 

4  wire,  single  phase 11.1% 

4  wire,  two  phase 50.0% 

3  wire,  two  phase 50.0%  with 

middle  wire   75   % 

4  wire,  three  phase,  with  neutral.  .  1 6.6% 
3   wire,  three  phase 50.0% 

All  wires  of  each  system ;  except  3  wire  two  phase ; 
considered  of  same  size. 

We  will  now  take  an  example  in  each  system  and 
show  how  to  calculate  the  wire  size. 

Three  Phase,  Three  Wire.  What  size  wire 
should  we  use  to  run  1-220  volt,  30  horsepower  in- 
duction motor;  and  light  102-220  volt,  60  watt 
mazda  lamps ;  a  distance  of  400  feet  to  the  center 
of  distribution  with  the  loss  of  7  volts? 

Let  us  refer  to  the  table  on  page  72.  Here  we 
see  that  the  amperes  per  phase  (same  as  amperes 
per  terminal)  of  a  3  phase,  220  volt,  30  H.P.  motor 
is  81.  We  must  calculate  the  amperes  per  phase 
for  the  lamps  by  using  this  formula : — 

total  watts  of  lamps 
Amperes  - 

1-73   X   volts 

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74 


In  this  case  there  are  102-60  watt  lamps  to  be 
burned  at  220  volts,  therefore  the 

102  X  60 

Amperes  per  phase  for  lamps  =  -          •=  16 

1.73  X  220 

Adding  this  to  the  81  amperes  for  the  motor  we 
have  81  +  16  =  97  for  the  total  amperes  per  phase. 
Now  let  us  look  at  the  wiring  table  for  three  phase 
three  wire  circuits  on  page  74.  It  says  at  the  top 
of  this  page  "multiply  current  in  amperes  per  phase 
by  single  distance  (in  feet)  and  refer  to  the  nearest 
number  under  column  of  Actual  Volts  Lost,  to  find 
size  of  wire."  Following  these  directions:— 

97  X  400  =  38,800;  under  column  of  7  volts  lost, 
the  nearest  number  is  39,800,  and  following  hori- 
zontally to  the  left,  under  column  headed  "Size  B. 
&  S."  we  find  that  No.  o  wire  is  our  size,  and  since 
the  allowable  carrying  capacity  is  127  amperes,  this 
size  is  permissible. 

Two  Phase,  Three  Wire.  What  size  wire 
should  we  use  to  run  50-40  watt  tungsten  lamps 
and  i-io  H.P.  induction  motor,  220  volt  service,  a 
distance  of  100  feet  from  the  center  of  distribution, 
with  a  loss  of  3  volts  ?  There  will  be  25  lamps  per 
phase  and  from  the  table  on  page  115  we  find  that 
the  current  taken  by  a  40  watt,  220  volt  tungsten 
lamp  is  .1818  amperes;  25  of  these  lamps  takes 
25  X  .1818  =  9.09  amperes.  Referring  to  the 
table  on  page  72  we  note  that  the  amperes  per  phase 
of  a  10  H.P.,  220  volt,  2  phase  motor  is  25.  This, 
then,  gives  us  a  total  of  25  +  9.09  =.  34.09  amperes 
per  phase. 

76 


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Turning  to  page  76  and  following  the  directions 
given  at  the  top  of  the  table  there  given : — 

34.09  X  ioo  =  3409; 

under  the  column  of  3  volts  loss,  we  find  opposite 
the  nearest  number  (3690)  that  we  are  to  use  No.  6 
wire  for  the  two  outside  lines  and  No.  4  wire  for 
the  middle  one. 

Two  Phase,  Four  Wire.  For  this  system  of 
wiring  calculate  the  amperes  per  phase  the  same  as 
for  2  phase,  three  wire,  and  use  the  table  on  page 
70  to  find  the  size  of  wire.  In  the  above  problem 
under  2  phase,  three  wire,  if  we  were  to  run  a  2 
phase,  four  wire  service,  we  would  use  No.  6  wire 
for  each  line. 

Three  Phase,  Four  Wire,  With  Neutral.  This 
system  is  very  little  used  and  therefore  no  table  is 
given,  but  the  sizes  can  be  calculated  in  this  way : — 
Calculate  the  circular  mils  necessary  for  a  two  wire 
system  of  the  same  total  wattage,  distance,  volts 
lost  and  applied  voltage  and  take  as  size  for  each 
wire  1 6.1%.  For  example,  a  system  using  a  total 
of  10,000  watt,  at  220  volts,  500  feet,  and  10  volt 
drop,  circular  mils  for  two  wire  system  = 
10.8  X  2  X  500  X  45-5 

-  ( formula  given  on  page 
10 

160)   —  49,000.     16.1%  of  th^s  is  49,000  X   .161 
=  8,170.     From  table  on  page  74  we  find  that  the 
nearest  size  (larger)  is  No.  10  wire,  therefore  we 
must  use  four  wires  of  this  size. 

Single  Phase,  Two  Wire.    Calculate  for  this  the 
same  as  for  two  wire  D.  C,  using  the  table  on  page 

77 


70.  In  the  case  of  motors,  obtain  the  amperes  re- 
quired from  table  on  page  72. 

Single  Phase,  Three  Wire.  Calculate  the  size 
necessary  for  a  two  wire  system  of  same  power, 
voltage,  volts  lost,  and  distance,  and  take  three  wires 
of  one-quarter  the  size  thus  calculated  for  this  sys- 
tem. The  same  general  method  as  given  above  un- 
der Three  Phase,  Four  Wire. 

Single  Phase,  Four  Wire.  Calculate  the  size 
necessary  for  a  two  wire  system  of  same  power, 
voltage,  volts  lost,  and  distance,  and  take  11.1% 
of  the  result  for  each  wire  in  this  system.  The 
same  general  method  as  given  above  under  Three 
Phase,  Four  Wire. 


A  convenient  type  of  pocket  wire  gauge,  one- 
half  actual  size,  for  measuring  wire  from  No.  18 
to  No.  ooo  B.  &  S.  gauge.  On  the  front  is  given 
the  safe  carrying  capacity  of  copper  wires  in  am- 
peres, and  on  the  reverse  side  the  approximate 
decimal  equivalent  of  the  various  sizes  of  wires. 

78 


Installation  of  Wires.  All  wiring,  when  not  en- 
closed in  approved  conduit,  moulding  or  armored 
cable,  should  be  kept  free  from  contact  with  gas, 
water  or  other  metallic  piping,  or  any  other  conduct- 
ors or  conducting  material  which  they  may  cross, 
by  some  continuous  and  firmly  fixed  non-conductor, 
creating  a  separation  of  at  least  two  inches,  and  in 
wet  places  should  be  arranged  so  that  an  air  space 
will  be  left  between  conductors  and  pipes  in  cross- 
ing, and  the  former  should  be  run  in  such  a  way 
that  they  cannot  come  in  contact  with  the  pipe  ac- 
cidentally. Where  one  wire  crosses  another  wire 
the  best  and  usual  means  of  separating  them  is  by  a 
porcelain  tube  on  one  of  the  wires.  The  tubing 
should  be  prevented  from  moving  out  of  place  either 
by  a  cleat  or  knob  on  each  end,  or  by  taping  it. 

The  same  method  may  be  adopted  where  wires 
pass  close  to  iron  pipes,  beams,  etc.,  or,  where  the 
wires  are  above  the  pipes,  as  is  generally  the  case, 
ample  protection  can  frequently  be  secured  by  sup- 
porting the  wires  with  a  porcelain  cleat  placed  as 
nearly  above  the  pipe  as  possible. 

Wires  should  be  run  over  rather  than  under  pipes 
upon  which  moisture  is  likely  to  gather,  or  which 
by  leaking  might  cause  trouble  on  a  circuit.  No 
smaller  size  than  No.  14  B.  &  S.  gauge  should  ever 
be  used  for  any  lighting  or  power  work,  not  that  it 
may  not  be  electrically  large  enough  but  on  ac- 
count of  its  mechanical  weakness  and  liability  to  be 
stretched  or  broken  in  the  ordinary  course  of  usage. 
Smaller  wire  may  be  used  for  fixture  work,  if  pro- 
vided with  approved  rubber  insulation. 

Wires  should  never  be  laid  in  or  come  in  contact 

7t 


with  plaster,  cement  or  any  finish,  and  should  never 
be  fastened  by  staples,  even  temporarily,  but  always 
supported  on  porcelain  or  glass  insulators  or  cleats 
which  will  separate  the  wires  at  least  one-half  inch 
from  the  surface  wired  over  and  keep  the  wires  not 
less  than  two  and  one-half  inches  apart;  three  wire 
cleats  may  be  used  when  the  neutral  wire  is  run  in 
the  center  and  at  least  two  and  one-half  inches  sep- 
arate the  two  outside  or  -j-  and  —  wires.  This  style 
of  wiring  is  intended  for  low  voltage  systems  (300 
volts  or  less),  and  when  it  is  all  open  work,  rubber 
covered  wire  is  not  necessary  as  "weatherproof" 
wire  may  be  used.  Weatherproof  wire  should  not 
be  used  in  moulding.  Wires  should  not  be  fished 
between  floors,  walls  or  partitions  or  in  concealed 
places. 

Twin  wires  should  never  be  used,  except  in  con- 
duits; they  are  always  unsafe  for  light  or  power 
circuits  on-  account  of  the  short  distance  between 
them. 

All  wiring  should  be  protected  on  side  walls  from 
mechanical  injury.  This  may  be  done  by  putting 
a  substantial  boxing  about  the  wires,  allowing  an  air 
space  of  one  inch  around  the  conductors  and  closed 
at  the  top  (the  wire  passing  through  bushed  holes) 
and  the  boxing  extending  about  five  feet  above  the 
floor.  Sections  of  metal  conduit  may  be  used  (the 
wire  being  protected  by  approved  flexible  tubing), 
and  in  most  cases  this  practice  is  preferable.  All 
bushings  should  be  made  of  non-combustible,  non- 
absorptive  insulating  material  such  as  glass  or  por- 
celain and  should  be  used  wherever  wires  go 
through  walls,  floors,  timbers  or  partitions.  They 

80 


CARRYING    CAPACITIES    AND    DIMENSIONS    OF    WIRES 

AND    CABLES. 
As   adopted  by  the   National  Board   of  Fire    Underwriters   of   the 

United    States. 
For  further   dimensions    of  bare   and  insulated    wires,  see   Index. 


an 

««  £1 

6 

M 

5 

S§c 

u 
v  . 

w  <_, 

t-  V 

£  c/i 

, 

5 

rt 

QJ  u 

SN 

P 

££j; 

£| 

M  "^ 

V 

•*! 

"<£g 

si* 

j§§« 

S.O 

SB 

o 

i 

3 

1 

6$£ 

Si 

gss 

^S 

fc3 

5 

u 

£^- 

*£ 

18 

40 

1  624 

_ 

3 

6.385 

4.9 

203.40 

16  

51 

2  583 

10 

a 

4.016 

7.8 

127.90 

14  

64 

4  107 

15 

2.525 

12.4 

80.44 

12 

81 

6  530 

")  /) 

20 

1.588 

19.7 

50.59 

10  

102 

10  380 

30 

25 

.999 

31.4 

31.82 

8 

128 

16  510 

50 

35 

.628 

49.9 

20.01 

6  

162 

26  250 

70 

50 

.395 

79.4 

12.58 

« 

182 

33  100 

80 

55 

.313 

100.2 

9.{/8 

4  

204 

41  740 

,   90 

70 

.248 

126.4 

7.91 

3 

229 

52  630 

100 

80 

.197 

159.3 

6.27 

258 

66  370 

125 

90 

.156 

200.9 

4.97 

i!!!!! 

289 

83690 

150 

100 

.124 

253.3 

3.94 

o  

325 

105  500 

200 

125 

.098 

319.5 

3.18 

00 

365 

133  100 

225 

150 

077 

402.8 

2.48 

000  

410 

167  800 

275 

175 

'.062 

507.9 

1.96 

0000  

460 

211  600 

325 

225 

.049 

640.9 

1.50 

Cables... 

450 

200  000 

300 

200 

.0532 

800 

630 

300  000 

400 

275 

.0335 

932 

oT 

"  .  .  ! 

727 

400  000 

500 

325 

.0251 

1:242 

I 

«« 

814 

500  000 

600 

400 

.0201 

1553 

* 

"  '.'.'. 

892 

600  000 

680 

450 

.0166 

1863 

«« 

964 

700  000 

760 

500 

.0143 

2174 

•X3  . 

44  !  !  '. 

1030 

800  000 

840 

550 

•   .0125 

2474 

•So 

" 

1092 

900  000 

920 

600 

.0111 

2795 

si 

•< 

1152 

1  000  000 

1000 

650 

.0100 

3106 

45  « 

" 

1209 

1  100  000 

1080 

690 

.0091 

3416 

«<-i  *" 

"  '.'.'. 

1263 

1  200  000 

1150 

730 

.0083 

3727 

0  bj, 

" 

1314 

1  300  000 

1220 

770 

.0076 

4038 

422. 

"  .  .  ! 

1364 

1  400  000 

1290 

810 

.0071 

4348 

"  ... 

1413 

1  500  000 

1360 

850 

.0066 

4658 

"C  an 

* 

«< 

1459 

1  600  000 

1430 

890 

.0062 

4968 

" 

1504 

1  700  000 

1490 

930 

.0058 

5278 

LI 

o 

"  .  '.  1 

1548 

1  800  000 

1550 

970 

.0055 

5588 

£ 

"  .  .  ! 

1572 

1  900  000 

1610 

1010 

.0052 

5898 

"  ... 

1630 

2  000  000 

1670 

1050 

.0050 

6208 

The  lower  current  carrying  limit  (fifth  column)  is  specified  for 
rubber-covered  wires  to  prevent  gradual  deterioration  of  the  high 
insulations  by  the  heat  of  the  wires,  but  not  from  fear  of  igniting 
the  insulation. 

The  carrying  capacity  of  Nos.  18  and  16  B.  &  S.  gauge  wire  is 
given,  but  no  smaller  than  No.  14  should  be  used  for  general  wiring 


purposes. 


81 


TENSILE  STRENGTH  OF  COPPEE  WIRE. 


Breaking:  weight, 
Pounds. 

Breaking  weight. 
Pounds. 

Numbers, 

Numbers, 

B.  &  S.  G. 

B.  &  S.  G. 

Hard- 

An- 

Hard- 

An- 

drawn. 

nealed. 

drawn  . 

nealed 

0000 

8310 

5650 

9 

616 

349 

000 

6580 

4480 

10 

489 

277 

00 

5226 

3553 

11 

388 

219 

0 

4558 

2818 

12 

307 

174 

1 

3746 

2234 

13 

244 

138 

2 

3127 

1772 

14 

193 

109 

3 

2480 

1405 

15 

153 

87 

4 

1967 

1114 

16 

133 

69 

5 

1559 

833 

17 

97 

55 

6 

1237 

700 

18 

77 

43 

7 

980 

555 

•      19 

61 

34 

8 

778 

440 

20 

48 

27 

The  strength  of  soft  copper  wire  varies  from 
32,000  to  36,000  pounds  per  square  inch,  and  of 
hard  copper  wire  from  45,000  to  68,000  pounds  per 
square  inch,  according  to  the  degree  of  hardness. 

EQUIVALENT  CROSS  SECTIONS  OF  WIRES. 
BROWN  &  SHAKP  GAUGE. 


0000 

2^  0 

4—  3 

8—  6 

16-  9 

32—12 

64—15 

128—18 

000 

2-  1 

4—  4 

8—  7 

16—10 

32-13 

64—16 

CO 

2-  2 

4—  6 

8—  8 

16—11 

32-14 

64-17 

1  and  3 

0 

2—  3 

4—  6 

8-  9 

16—12 

32—15 

64—18 

2           4 

1 

2—  4 

4—  7 

8—10 

16-13 

32—16 

3           5 

2 

2-5 

4—  8 

8-11 

16—14 

32-17 

4           6 

3 

2-  6 

4-9 

8—12 

16—15 

32—18 

5           7 

4 

2—  7 

4—10 

8—13 

16—16 

6           8 

5 

2—  8 

4—11 

8—14 

16—17 

7           9 

6 

2—  9 

—12 

8-15 

16-18 

8          10 

7 

2—10 

—13 

8-16 

9          11 

3 

2—11 

—14 

8—17 

10        12 

9 

2—12 

—15 

8-18 

11        13 

10 

2-13 

—18 

12        14 

11 

2-14 

4—17 

13        15 

12 

2-15 

4-18 

14        16 

13 

2-16 

15        17 

14 

2—17 

16       18 

15 

2-18 

82 


should  be  long  enough  to  bush  the  entire  length  of 
the  hole  in  one  continuous  piece,  or  else  the  hole 
must  first  be  bushed  by  a  continuous  waterproof 
tube.  This  tube  may  be  a  conductor,  such  as  iron 
pipe,  but  in  that  case  the  wire  must  be  protected  by 
approved  flexible  tubing  extending  far  enough  to 
keep  the  wire  absolutely  out  of  contact  with  the 
pipe. 

If,  however,  iron  pipes  are  used  with  alternating 
currents,  the  two  or  more  wires  of  a  circuit  should 


Porcelain   Insulating  Tube  for  partition  and  walls. 

always  be  placed  in  the  same  conduit.  If  plain  iron 
pipe  be  used  the  insulation  of  that  portion  of  each 
wire  within  the  pipe  should  be  reinforced  by  a  tough 
approved  flexible  tubing  projecting  beyond  the  iron 
tubing. 

When  crossing  floor  timbers  in  cellars  or  in 
rooms  when  they  might  be  exposed  to  injury,  wires 
should  be  attached,  by  their  insulating  supports,  to 
the  under  side  of  wooden  strips  not  less  than  one- 
half  inch,  in  thickness  and  not  less  than  three  inches 
wide. 


When  wires  are  run  immediately  under  roofs,  or 
in  proximity  to  water 'tanks  or  pipes  they  will  be 
considered  as  exposed  to  moisture  and  care  should 
be  taken  as  described  on  pages  87  and  103. 
SWITCHES,  CUT-OUTS,  CIRCUIT-BREAK- 
ERS, ETC. 

On  constant  potential  circuits,  all  service  switches 
and  all  switches  controlling  circuits  supplying  cur- 
rent to  motors  or  heating  devices,  and  all  fuses 
should  be  so  arranged  that  the  fuses  will  protect 
and  the  opening  of  the  switch  will  disconnect  all 
of  the  wires;  that  is,  in  the  two-wire  system  the 
two  wires,  and  the  three-wire  system  the  three 
wires,  should  be  protected  by  the  fuses  and  discon- 
nected by  the  operation  of  the  switch. 

When  installed  without  other  automatic  overload 
protective  devices  automatic  overload  circuit  break- 
ers should  have  the  poles  and  trip  coils  so  arranged 
as  to  afford  complete  protection  against  overloads 
and  short  circuits,  and  if  also  used  in  place  of  the 
switch  should  be  so  arranged  that  no  one  pole  can 
be  opened  manually  without  disconnecting  all  the 
wires. 

This,  of  course,  does  not  apply  to  the  grounded 
circuit  of  street  railway  systems. 

They  should  not  be  placed  where  exposed  to  me- 
chanical injury  nor  in  the  immediate  vicinity  of 
easily  ignitible  stuff  or  where  exposed  to  inflam- 
mable gases  or  dust  or  to  flyings  of  combustible 
material. 

Where  the  occupancy  of  a  building  is  such  that 
switches,  cut-outs,  etc.,  cannot  be  located  so  as  not 
to  be  exposed  as  above,  they,  should  be  enclosed 

84 


in  approved  dust-proof  cabinets  with  self-closing 
doors,  except  oil  switches  and  circuit  breakers 
which  have  dust-tight  casings. 

They  should  also,  when  exposed  to  dampness, 
either  be  enclosed  in  a  moisture-proof  box  or 
mounted  on  porcelain  knobs.  The  cover  of  the  box 
should  be  so  made  that  no  moisture  which  may 
collect  on  the  top  or  sides  of  the  box  can  enter  it. 

Time  switches,  sign  flashers  and  similar  appli- 
ances should  be  of  approved  design  and  enclosed 
in  approved  cabinets. 

Series  Arc  Lamp  Wiring.  All  wiring  in  build- 
ings for  constant  current  series  arc  lighting  should 
he  with  approved  rubber  covered  wire  and  the  cir- 
cuit arranged  to  enter  and  leave  the  building 
through  an  approved  double  contact  service  switch, 
which  means  a  switch  mounted  on  a  non-combust- 
ible, non-absorptive  insulating  base  and  capable  of 
closing  the  main  circuit  and  disconnecting  the 
branch  wires  when  turned  "off";  this  switch  must 
be  so  constructed  that  it  will  be  automatic  in  action, 
not  stopping  between  points  when  started,  and 
must  prevent  an  arc  between  points  under  all  cir- 
cumstances, and  must  indicate,  upon  inspection, 
whether  the  current  be  "on"  or  "off."  Such  a 
switch  is  necessary  to  cut  the  high  voltage  current 
completely  out  of  the  building  by  firemen  in  case  of 
fire  or  when  it  becomes  necessary  to  make  any 
changes  in  the  lamps  or  wiring.  It  should  be  in  a 
non-combustible  case. 

This  class  of  wiring  should  never  be  concealed 
or  incased  except  when  requested  by  the  Electrical 
Inspector,  and  should  always  be  rigidly  supported 

85 


on  porcelain  or  glass  insulators  which  will  separate 
the  wiring  at  least  one  inch  from  the  surface  wired 
over,  and  should  be  kept  at  least  eight  inches  from 
each  other.  No  wires  carrying  a  potential  of  over 
3,500  volts  should  be  carried  into  or  over  any  build- 
ing except  central  stations  and  sub-stations.  All 
arc  light  wiring  should,  on  side  walls,  be  protected 
from  mechanical  injury  by  a  substantial  boxing, 
retaining  an  air  space  of  one  inch  around  the  con- 
ductors, closed  at  the  top  (the  wires  passing 
through  bushed  holes),  and  extending  not  less  than 
seven  feet  from  the  floor.  When  crossing  floor 
timbers  in  cellars,  or  in  rooms  where  they  might  be 
exposed  to  injury,  wires  should  be  attached  by  their 
insulating  supports  to  the  under  side  of  a  wooden 
strip  not  less  than  one-half  an  inch  in  thickness. 
Instead  of  the  running-boards,  guard  strips  on  each 
side  of  and  close  to  the  wires  will  be  sufficient. 
These  strips  to  be  not  less  than  seven-eighths  of  an 
inch  in  thickness  and  at  least  as  high  as  the  insu- 
lators. 

Except  on  joisted  ceilings,  a  strip  one-half  of  an 
inch  thick  is  not  considered  sufficiently  stiff  and 
strong.  For  spans  of  say  eight  or  ten  feet,  where 
there  is  but  little  vibration,  one-inch  stock  is  gen- 
erally sufficiently  stiff ;  but  where  the  span  is  longer 
than  this  or  there  is  considerable  vibration,  still 
heavier  stock  should  be  used. 

Series  arc  lamps  should  be  isolated  from  inflam- 
mable material,  and  should  be  provided  at  all  times 
witn  a  glass  globe  surrounding  the  arc,  and  securely 
fastened  upon  a  closed  base.  Broken  or  cracked 
globes  should  not  be  used. 

86  '     . 


They  should  be  provided  with  a  wire  netting 
(having  a  mesh  not  exceeding  one  and  one-fourth 
inches)  around  the  globe,  and  an  approved  spark 
arrester  when  readily  inflammable  material  is  in  the 
vicinity  of  the  lamps,  to  prevent  escape  of  sparks  of 
carbon  or  melted  copper.  It  is  recommended  that 
plain  carbons,  not  copper-plated,  be  used  for  lamps 
in  such  places. 

Outside  arc  lamps  should  be  suspended  at  least 
eight  feet  above  sidewalks.  Inside  arc  lamps  should 
be  placed  out  of  reach  or  suitably  protected. 

Arc  lamps,  when  used  in  places  where  they  are 
exposed  to  flyings  or  easily  inflammable  material, 
should  have  the  carbons  enclosed  completely  in  a 
tight  globe  in  such  manner  as  to  avoid  the  necessity 
for  spark  arresters. 

"Enclosed  arc"  lamps,  having  tight  inner  globes, 
may  be  used  in  such  places. 
SERIES  INCANDESCENT  LAMP  WIRING. 

The  same  suggestions  given  for  the  wiring  for 
series  arc  lamps  should  apply  to  this  class  of  work 
as  well.  Each  series  incandescent  lamp  should  be 
provided  with  its  own  automatic  cut-out.  Each 
lamp  should  be  suspended  from  a  hanger-board  by 
a  rigid  tube. 

In  no  way  should  they  come  in  contact  with,  or 
be  connected  to,  gas  fixtures.  No  electro-magnetic 
device  for  switches  and  no  multiple-series  or  series- 
multiple  systems  of  lighting  should  be  used. 

Special  Wiring  for  damp  places  such  as  brew- 
eries, packing  houses,  stables,  dye  houses,  paper  or 
pulp  mills,  or  buildings  specially  liable  to  moisture 
or  acid  or  other  fumes  liable  to  injure  the  wires  or 

87 


their  insulation,  except  where  used  for  pendants 
should  always  be  done  with  approved  rubber  cov- 
ered wire,  and  rigidly  supported  on  porcelain  or 
glass  insulators  which  separate  the  wires  at  least 
one  inch  from  the  surface  wired  over  and  must  be 
kept  apart  at  least  two  and  one-half  inches.  The 
wire  in  such  damp  places  should  contain  no  splices 
as  it  is  almost  impossible  to  tape  a  splice  that  will 
prevent  acid  fumes  from  getting  at  the  copper 
surface. 

Wood  Moulding  Work  should  always  be  done 
with  approved  rubber-covered  wire  to  prevent  leak- 
age should  the  moulding  become  damp. 

This  class  of  work  should  never  be  done  in  con- 
cealed or  damp  places  for  fear  that  water  may  soak 
into  the  wood  and  cause  leakage  of  current  between 
the  wires,  burning  the  wood  and  starting  a  fire.  The 
action  of  the  current  in  a  case  like  this  is  to  very 
gradually  convert  the  wood  into  charcoal,  then  dry 
the  water  out  and  ignite  the  charcoal  thus  formed. 
Great  care  should  be  observed  in  driving  nails  into 
moulding  in  order  to  avoid  puncturing  the  insula- 
tion, and  possibly  grounding  the  circuit  in  a  way 
that  would  not  only  be  difficult  to  locate,  but  might 
cause  a  concealed  fire  back  of  the  plastering  or  wood 
work  to  which  the  moulding  is  attached. 

Wood  Moulding  should  be  made  of  hard  wood 
and  should  be  made  of  two  pieces,  a  backing  and 
capping,  so  constructed  as  to  thoroughly  encase  the 
wire.  It  should  provide  a  one-half  inch  tongue  be- 
tween the  conductors  and  a  solid  backing,  which 
under  the  grooves  should  not  be  less  than  three- 
eighths  of  an  inch  and  on  the  sides  not  less  than 


one-fourth  of  an  inch  in  thickness  and  be  able  to 
give  suitable  protection  from  abrasion.  All  wood 
mouldings  should  be  painted  with  two  coats  of 
waterproof  material  or  impregnated  with  a  moist- 
ure repellant.  Wood  moulding  should  never  be 
used  in  damp  places. 

Metal  Moulding  should  be  of  approved  make, 
should  be  constructed  of  iron  or  steel  with  backing 
at  least  .050  inch  in  thickness,  and  with  capping  not 
less  han  .040  inch  in  thickness,  and  so  construc- 
ted that  when  in  place  the  raceway  will  be  entirely 


Metal    Moulding. 

closed,  and  be  thoroughly  galvanized  or  coated  with 
an  approved  rust  preventative  both  inside  and  out 
to  prevent  oxidation.  Each  length  of  metal  mould- 
ing should  have  the  maker's  name  or  trade  mark 
stamped  in  the  metal,  and  only  approved  moulding 
should  be  used. 

Elbows,  couplings  and  all  other  similar  fittings 
should  be  constructed  of  at  least  the  same  thickness 
and  quality  of  metal  as  the  moulding  itself,  and  so 
designed  that  they  will  both  electrically  and  me- 
chanically secure  the  different  sections  together  and 

89 


maintain  the  continuity  of  the  raceway.  The  in- 
terior surfaces  should  be  free  from  burrs  or  sharp 
corners  which  might  cause  abrasion  of  the  wire 
coverings. 

All  outlets  should  be  so  arranged  that  the  con- 
ductors cannot  come  in  contact  with  the  edges  of 
the  metal,  either  of  capping  or  backing.  Specially 
designed  fittings  which  will  interpose  substantial 
barriers  between  conductors  and  the  edges  of  metal 
are  recommended. 

When  backing  is  secured  in  position  by  screws  or 
bolts  from  the  inside  of  the  raceway,  depressions 
should  be  provided  to  render  the  heads  of  the  fast- 
enings flush  with  the  moulding. 

Metal  mouldings  should  be  so  constructed  as  to 
form  an  open  raceway  to  be  closed  by  the  capping 
or  cover  after  the  wires  are  laid  in. 

No  moulding  work,  with  either  metal  or  wood, 
should  ever  be  done  in  damp  or  concealed  places,  or 
when  the  difference  of  potential  between  any  two 
wires  in  the  same  moulding  is  over  300  volts ;  metal 
mouldings  should  not  be  used  for  circuits  requiring 
more  than  1,320  watts  of  energy.  Alternating  cur- 
rent circuits  should  have  their  two  or  more  wires 
run  in  the  same  metal  moulding  for  inductive 
reasons. 

Concealed  Wiring  or  that  which  is  to  be  run 
between  walls  and  floors  and  through  joists,  should 
always  be  done  with  approved  rubber-covered  wire, 
and  should  be  rigidly  supported  on  porcelain  or 
glass  insulators  which  will  separate  the  wires  at 
least  one  inch  from  the  surface  wired  over,  and  the 
wires  kept  at  least  five  inches  apart,  and  where  it  is 


possible  wires  should  be  run  singly  on  separate 
timbers  or  joists. 

The  wires  should  be  separated  from  contact  with 
the  walls,  floor  timbers  and  partitions  through  which 
they  may  pass  by  non-combustible,  non-absorptive 
insulating  tubes,  such  as  glass  or  porcelain. 

Rigid  supporting  requires,  under  ordinary  condi- 
tions, where  wiring  along  flat  surface,  supports  at 
least  every  four  and  one-half  feet.  If  the  wires  are 
liable  to  be  disturbed  the  distance  between  supports 
should  be  shortened. 

At  distributing  centers,  outlets  or  switches  where 
space  is  limited  and  the  five-inch  separations  can- 
not be  maintained,  each  wire  should  be  separately 
encased  in  a  continuous  length  of  approved  flexible 
tubing. 


Approved   Flexible   Tubing. 

Wires  passing  through  timbers  at  the  bottom  of  plas- 
tered partitions  should  be  protected  by  an  additional  tube 
extending  at  least  four  inches  above  the  timber. 

When  in  a  concealed  knob  and  tube  system,  it  is  im- 
practicable to  place  the  whole  of  a  circuit  on  non-com- 
bustible supports  of  glass  or  porcelain,  that  portion  of  the 
circuit  which  cannot  be  so  supported  should  be  installed 
with  approved  metal  conduit,  or  approved  armored  cable 
except  that  if  the  difference  of  potential  between  the  wires 
is  not  over  300  volts,  and  if  the  wires  are  not  exposed  to 
moisture,  they  may  be  fished  if  separately  encased  in  ap- 
proved flexible  tubing,  extending  in  continuous  lengths 
from  porcelain  support  to  porcelain  support,  from  porce- 
lain support  to  outlet,  or  from  outlet  to  outlet. 

Wires  should  at  all  outlets,  except  where  conduit 

91 


is  used,  be  protected  by  approved  flexible  tubing,  ex- 
tending in  continuous  lengths  from  the  last  porce- 
lain support  to  at  least  one  inch  beyond  the  outlet. 
In  the  case  of  combination  fixtures  the  tubes  should 
extend  at  least  flush  with  outer  end  of  gas  cap. 

It  is  recommended  that  approved  outlet  boxes  or 
plates  be  installed  at  all  outlets  in  concealed  "knob 
and  tube"  work,  the  wires  to  be  protected  by  ap- 
proved flexible  tubing,  extending  in  continuous 
lengths  from  the  last  porcelain  support  into  the 
box.  METAL  CONDUIT  (RIGID). 

Every  length  of  approved  metal  conduit  (ten 
feet)  has  the  maker's  name  or  initials  stamped  in 
the  metal.  Metal  conduit  is  made  of  mild  steel  and 


Approved   Metal   Conduits. 

is  coated   with   enamel   or   rust   resisting  material. 


The  standard  lengths,  ten  feet  each,  are  furnished  in  fif- 
teen diameters  as  follows:  %,  ^,  j£,  ^,  :,  i*4,  iJ/£,  2,  2j/£, 
3.  3^>  4>  4/^>  5  and  6  inches.  Each  size  has  its  correspond- 
ing size  elbow,  coupling,  etc.  The  specifications  for  the 
construction  of  metal  conduit  are  numerous,  but  the  con- 
tractor or  wireman  need  not  bother  about  these  details — 
just  see  that  it  is  of  the  proper  size  and  bears  the  name 
or  initials  of  an  approved  maker. 

Flexible  Steel  Conduit  is  made  for  use  on  odd 
or  irregular  bends  or  for  inaccessible  places  "where 
the  rigid  conduit  could  only  be  installed  with  great 
difficulty.  It  is  furnished  in  any  lengths  desired 
and  in  nine  different  diameters  (inside),  5/16,  3/6, 
]/2,  %,  i,  i,T4?  I'/^j  2  and  2/4  inches. 

No  metal  conduit  with  an  inside  diameter  of  less  than 
one-half  inch  should  be  used.  All  conduit  work  should  be 
continuous  from  outlet  to  outlet  or  to  junction  boxes  or 
cabinets,  and  the  conduit  should  properly  enter,  and  be 
secured  to  all  fittings,  and  the  entire  system  mechanically 
secured  in  position. 

In  case  of  service  connections  and  main  runs, 
this  involves  running  each  conduit  continuously  into 
a  main  cut-out  cabinet  or  gutter  surrounding  the 
panelboard,  as  the  case  may  be. 

It  should  be  first  installed  as  a  complete  conduit 
system,  without  the  conductors. 

It  should  be  equipped  at  every  outlet  with  an  ap- 
proved outlet  box  or  plate.  At  exposed  ends  of 
conduit  (but  not  at  fixture  outlets)  where  wires 
pass  from  the  conduit  system  without  splice,  joint 
or  tap,  an  approved  fitting  having  separately  bushed 
holes  for  each  conductor  should  be  used. 

Outlet  plates  should  not  be  used  where  it  is  prac- 
ticable to  install  outlet  boxes. 

For  concealed  work  in  walls  and  ceilings  com- 
posed of  plaster  on  wooden  joists  or  stud  construe 

93 


tion,  outlet  boxes  or  plates  and  also  cut-out  cab- 
inets should  be  so  installed  that  that  the  front  edge 
will  not  be  more  than  one-fourth  inch  back  of  the 
finished  surface  of  the  plaster,  and  if  this  surface 
is  broken  or  incomplete  it  should  be  repaired  so 
that  it  will  not  show  any  gaps  or  open  spaces 
around  the  edges  of  the  outlet  box  or  plate  or  of 
the  cut-out  cabinet.  On  wooden  walls  or  ceilings, 
outlet  boxes  or  plates  and  cut-out  cabinets  should 
be  so  installed  that  the  front  edge  will  either  be 
flush  with  the  finished  surface  or  project  there- 
from. This  will  not  apply  to  concealed  work  in 
walls  or  ceilings  composed  of  concrete,  tile  or  other 
non-combustibile  material. 

In  buildings  already  constructed  where  the  con- 
ditions are  such  that  neither  outlet  box  nor  plate 
can  be  installed,  these  appliances  may  be  omitted, 
providing  the  conduit  ends  are  bushed  and  secured. 

It  is  suggested  that  outlet  boxes  and  fittings  hav- 
ing conductive  coatings  be  used  in  order  to  secure 
better  electrical  contact  at  all  points  throughout  the 
conduit  system. 

Metal  conduits  where  they  enter  junction  boxes, 
and  at  all  other  outlets,  etc.,  should  be  provided 
with  approved  bushings  or  fastening  plates  fitted 
so  as  to  protect  wire  from  abrasion,  except  when 
such  protection  is  obtained  by  the  use  of  approved 
nipples,  properly  fitted  in  boxes  or  devices. 

The  metal  of  the  conduit  should  be  permanently 
and  effectually  grounded  to  water  piping,  gas  pip- 
ing or  other  suitable  grounds,  provided  that  when 
connections  are  made  to  gas  piping,  they  are  on 
the  street  side  of  the  meter.  If  the  conduit  system 

94 


consists  of  several  separate  sections,  the  sections 
should  be  bonded  to  each  other,  and  the  system 
grounded,  or  each  section  may  be  separately 
grounded,  as  required  above.  Where  short  sections 
of  conduit  (or  pipe  of  equivalent  strength)  are  used 
for  the  protection  of  exposed  wiring  on  side  walls, 
the  conduit  or  pipe  need  not  be  grounded. 

Conduits  and  gas  pipes  should  be  securely  fast- 
ened in  outlet  boxes,  junction  boxes  and  cabinets, 
so  as  to  secure  good  electrical  connections. 

If  conduit,  couplings,  outlet  boxes,  junction 
boxes,  cabinets  or  fittings,  having  protective  coat- 
ing of  non-conducting  material  such  as  enamel  are 
used,  such  coating  should  be  thoroughly  removed 
from  threads  of  both  couplings  and  conduit,  and 
such  surfaces  of  boxes,  cabinets  and  fittings  where 
the  conduit  or  ground  clamp  is  secured  in  order  to 
obtain  the  requisite  good  connection.  Grounded 
pipes  should  be  cleaned  of  rust,  scale,  etc.,  at  place 
of  attachment  of  ground  clamp. 

Connections  to  grounded  pipes  and  to  conduit 
should  be  exposed  to  view  or  readily  accessible,  and 
should  be  made  by  means  of  approved  ground 
clamps  to  which  the  ground  wires  should  be  sol- 
dered. 

Ground  wires  should  be  of  copper,  at  least  No. 
10  B.  &  S.  gage  (where  largest  wire  contained  in 
conduit  is  not  greater  than  No.  o  B.  &  S.  gage),  and 
need  not  be  greater  than  No.  4  B.  &  S.  gage  (where 
largest  wire^  contained  in  conduit  is  greater  than 
No.  o  B.  &  S.  gage).  They  should  be  protected 
from  mechanical  injury. 

All  elbows  or  bends  should  be  so  made  that  the 

95 


conduit  •  will  not  be  injured.  The  radius  of  the 
curve  of  the  inner  edge  of  any  elbow  not  to  be  less 
than  three  and  one-half  inches.  There  should  be 
not  more  than  the  equivalent  of  four  quarter  bends 
from  outlet  to  outlet,  the  bends  at  the  outlets  not 
being  counted. 

CONDUIT    WIRING. 

All  conductors  for  this  class  of  work  should  be 
approved  rubber  covered. 

Single  wire  for  conduits  must  comply  with  the 
requirements  and  in  addition  there  should  be  a 
second  outer  fibrous  covering,  at  least  one  thirty- 
second  of  an  inch  in  thickness  for  wires  larger  than 
No.  10  B.  &  S.  gage,  and  at  least  one  sixty-fourth 
of  an  inch  in  thickness  for  wires  No.  10  B.  &  S. 
gage'  or  less  in  size;  this  fibrous  covering  to  be 
sufficiently  tenacious  to  withstand  abrasion  of  being 
hauled  through  the  metal  conduit. 

For  twin  or  duplex  wires  in  conduit  each  con- 
ductor must  comply  with  requirements  and  in  addi- 
tion there  must  be  a  second  outer  fibrous  covering, 
at  least  one  thirty-second  of  an  inch  in  thickness 
for  wires  larger  than  No.  10  B.  &  S.  gage,  and  at 
least  one  sixty-fourth  of  an  inch  in  thickness  for 
wires  No.  10  B.  &  S.  gage  or  less  in  size;  this 
fibrous  covering  to  be  sufficiently  tenacious  to  with- 
stand abrasion  of  being  hauled  through  the  metal 
conduit. 

For  concentric  wire,  the  inner  conductor  should 
comply  with  the  requirements  and  there  should  be 
outside  of  the  outer  conductor  the  same  insulation 
as  on  the  inner,  the  whole  to  be  covered  with  a  sub- 
stantial braid,  which  should  be  at  least  one  thirty- 

96 


second  of  an  inch  in  thickness,  and  sufficiently 
tenacious  to  withstand  the  abrasion  of  being  hauled 
through  the  metal  conduit. 

The  braids  or  tapes  should  be  properly  saturated 
with  a  preservative  compound. 

The  braid  or  tape  required  around  each  conductor 
in  duplex,  twin  and  concentric  cables  is  to  hold  the 
rubber  insulation  in  place  and  prevent  jamming  and 
flattening.  No  wires  should  be  drawn  into  conduits 
until  all  mechanical  work  on  the  building  has  been 
done. 

Conductors  in  vertical  conduit  risers  should  be 
supported  within  the  conduit  system  in  accordance 
with  the  following  table: 

No.  14  to  o  every  100  feet. 

No.  oo  to  oooo  .every  80  feet. 

oooo  to  350,000  C.  M.  every  60  feet. 

350,000  C.  M.  to  500,000  C.  M.  every  50  feet. 

500,000  C.  M.  to  750,000  C.  M.  every  40  feet. 

750,000  C.  M.  every  35  feet. 

The  following  methods  of  supporting  cables  are 
recommended : 

1.  A  turn  of  90  degrees  in  the  conduit  system 
will  constitute  a  satisfactory  support. 

2.  Junction  boxes  may  be  inserted  in  the  con- 
duit system  at  the  required  intervals,  in  which  in- 
sulating supports  of  approved  type  must  be  installed 
and  secured  in  a  satisfactory  manner  so  as  to  with- 
stand the  weight  of  the  conductors  attached  thereto, 
the  boxes  to  be  provided  with  proper  covers. 

3.  Cables  may  be  supported  in  approved  junc- 
tion boxes  on  two  or  more  insulating  supports  so 
placed  that  the  conductors  will  be  deflected  at  an 

97 


angle  of  not  less  than  90  degrees,  and  carried  a 
distance  of  not  less  than  twice  the  diameter  of  the 
cable  from  its  vertical  position.  Cables  so  sus- 
pended may  be  additionally  secured  to  these  insu- 
lators by  tie  wires. 

For  alternating  systems,  the  two  or  more  wires 
of  a  circuit  should  be  drawn  in  the  same  conduit. 

It  is  suggested  that  this  be  done  for  direct  cur- 
rent systems  also,  so  that  they  may  be  changed  to 
alternating  systems  at  any  time,  induction  troubles 
preventing  such  a  change  if  the  wires  are  in  sepa- 
rate conduits. 

Fixtures  should,  when  supported  from  the  gas 
piping  of  a  building,  be  insulated  from  the  gas 
pipe  system  by  means  of  approved  insulating  joints 
(see  page  107)  placed  as  close  as  possible  to  the 
ceiling,  and  the  wires  near  the  gas  pipe  above  the 
insulating  joint  should  be  protected  from  possible 
contact  by  the  use  of  porcelain  tubes. 

All  burrs  or  fins  should  be  removed  from  the  fix- 
tures before  the  wires  are  drawn  in.  The  tendency 
to  condensation  within  the  pipes  should  be  guarded 
against  by  sealing  the  upper  end  of  the  fixture. 

In  combination  fixtures,  where  the  wiring  is  con- 
cealed between  the  inside  pipe  and  outer  casing,  the 
space  between  pipe  and  casing  should  be  at  least  a 
quarter  of  an  inch  to  allow  plenty  of  room  for  the 
insulation  of  the  wires  without  jamming. 

Fixtures  should  be  tested  for  "contacts"  between 
conductors  and  fixtures,  for  "short-circuits"  and  for 
ground  connections  before  it  is  connected  to  its 
supply  conductors. 

Ceiling  blocks  of  fixtures  should  be  made  of  in- 


sulating  material ;  if  not,  the  wires  in  passing 
through  the  plate  should  be  surrounded  by  porce- 
lain tubes,  which  should  extend  below  the  insulating 
joint. 

When  fixtures  have  canopies  against  plaster  in 
fireproof  buildings,  or  where  wire  lath  or  metal 
ceiling  or  metal  wall  finish  is  used,  the  canopies 
should  be  thoroughly  and  permanently  insulated 
from  such  walls  or  ceilings  by  approved  canopy 
insulators.  (See  illustration  on  page  107.) 

Rosettes.  These  fittings  should  not  be  located 
where  inflammable  flyings  or  dust  will  accumulate 
on  them.  Bases  should  be  high  enough  to  keep  the 
wires  and  terminals  at  least  one-half  inch  from  the 
surface  to  which  the  rosette  is  attached. 

Terminals  with  a  turned  up  lug  to  hold  the  wire 
or  cord  should  be  used,  and  in  no  case  must  the 
wire  be  cut  or  injured.  Fused  rosettes  are  not  ad- 
vised for  use  where  cords  can  be  properly  protected 
by  line  cut-outs,  and  where  necessary  those 
equipped  with  enclosed  fuses  are  recommended.  If 
fused  rosettes  are  used  the  next  fuses  back  should 
not  be  over  25  amperes  capacity. 

Fixture  Wiring  should  be  done  with  approved 
fixture  wire.  The  voltage  should  never  exceed  300 
on  wires  in  fixtures. 

Although  No.  18  "rubber  covered"  is  allowable 
in  fixture  work,  it  is  preferable  to  use  nothing 
smaller  than  No.  16,  if  practicable,  for  mechanical 
reasons.  Supply  conductors,  and  especially  the 
splices  to  fixture  wires,  should  be  kept  clear  of  the 
grounded  part  of  gas  pipes,  and  where  shells  are 
used  the  latter  should  have  area  enough  to  prevent 

99 


pressing  the  wires  against  the  gas  pipe  when  finally 
in  place. 

Flexible  Cord  should  be  made  of  stranded  cop- 
per conductors,  no  single  strand  should  be  larger 
than  No.  26  or  smaller  than  No.  36  (B.  &  S.  gauge) 
and  each  conductor  should  be  covered  by  an  ap- 
proved insulation  and  be  protected  from  mechanical 
injury  by  a  tough  braided  outer  covering.  When 
used  for  pendant  lamps  it  should  hang  freely  in  air 
and  so  placed  that  there  is  no  chance  of  its  coming 
in  contact  with  anything  excepting  the  lamp  socket 
to  which  it  is  attached  and  the  rosette  from  which 
it  hangs.  Each  stranded  conductor  should  have  a 
carrying  capacity  equivalent  to  not  less  than  a  No. 
1 8  (B.  &  S.  gauge)  wire.  The  covering  of  the 
stranded  wires  for  flexible  cord  should  first  have  a 
tight,  close  wind  of  fine  cotton,  which  is  intended  to 
prevent  any  broken  strand  from  piercing  the  insu- 
lation and  causing  a  short  circuit  or  ground.  Sec- 
ondly it  should  have  a  solid  waterproof  insulation 
at  least  one  thirty-second  of  an  inch  thick.  The 
outer  protecting  braiding  should  be  so  put  on  and 
sealed  in  place  that  when  cut  it  will  not  fray  out. 

Approved  flexible  cord  may  be  had  from  any  of 
the  makers  mentioned  on  pages  66  and  67. 

Flexible  cord  should  not  be  used  as  a  support  for 
clusters,  as  it  is  not  strong  enough;  and  it  should 
never  be  used  for  anything  other  than  pendants, 
wiring  of  fixtures  and  portable  lamps,  portable 
motors  or  small  light  electrical  apparatus.  Where 
used  for  "portables"  it  should  have  a  special  outer 
covering. 

Flexible  cord  should  never  be  used  in  show  win- 
100 


dows,  as  a  defective- piece  might  cauce «a  -short  cir- 
cuit and  set  fire  to  flints}'  'material  or  decorations. 
Many  fires  have  been  caused  by  the  use  of  flexible 
cord  in  show  windows,  where  handkerchiefs,  deco- 
rations, etc.,  have  been  pinned  to  the  cord.  When 
the  current  is  "turned  on"  short  circuits  are  caused 
by  the  pins,  and  a  fire  is  the  result.  Armored 
cables,  however,  may  be  used  for  this  class  of  work 
and  are  made  by  the  following  companies  : 

Boston  Ins.  Wire  &  Cable  Co.,  Boston;  Columbia  Metal 
Hose  Wks.,  Bayonne,  N.  J. ;  Eastern  Flexible  Conduit  Co., 
Brooklyn,  N.  Y. ;  Flexible  Conduit  Co.,  Pen  Yan,  N.  Y. ; 
National  Metal  Molding  Co.,  Pittsburg,  Pa.;  Pratt  Chuck 
Co.,  Frankfort,  N.  Y. ;  Safety-Armorite  Conduit  Co., 
Pittsburg,  Pa.;  Sprague  Electric  Wks.  of  G.  E.  Co.,  New 
York;  Trenton  Electric  &  Conduit  Co.,  Trenton,  N.  J. ; 
Western  Conduit  Co.,  Youngstown,  O. 

Insulating  bushings  should  be  used  where  cords  enter 
lamp  sockets  and  desk  stand  lamps. 

Flexible  cord  should  be  so  suspended  that  the  entire 
weight  of  the  socket,  lamp  and  shade  will  be  borne  by 
knots  under  the  bushing  in  the  socket,  and  above  the 
point  where  the  cord  comes  through  the  ceiling  block  or 
rosette,  in  order  that  the  strain  may  be  taken  from  the 
joints  and  binding  screws.  It  is  good  practice  to  always 
solder  the  ends  of  flexible  cords  which  are  going  under 
binding  screws,  as  it  holds  the  strands  together  and  pre- 
vents the  pressure  of  the  screws  from  forcing  the  strands 
from  under  them,  and  against  the  shell  of  the  socket, 
causing  a  ground  on  the  shell,  or  shore  circuit. 

Where  it  becomes  necessary  to  solder  a  great  number 
of  ends,  as  may  be  required  when  wiring  a  factory,  use 
a  small  pot  of  melted  solder  and  dip  the  ends  of  the 
wire,  which  have  all  been  previously  cut  to  the  proper 
length  and  fluxed  with  a  good  soldering  paste  or  solution. 
101 


Standard, L4n>p  .SocketsshouM  be  plainly  marked 
with  the'  watts  and  volts  which  apply  to  their  class 
and  with  either  the  manufacturer's  name  or  regis- 
tered trade  mark.  The  inside  of  the  shell  of  the 
socket  should  have  an  insulating  lining  which 
should  absolutely  prevent  the  shell  from  becoming 
a  part  of  the  circuit  even  though  a  wire  or  strand 
inside  the  socket  should  become  loose  or  come  out 
from  under  a  binding  screw.  This  insulating  lin- 
ing should  be  at  least  one-thirty-second  of  an  inch 
thick  and  of  a  tough  and  tenacious  material. 

Special  Lamp  Sockets.    In  rooms  where  inflam- 


Waterproof  Keyless  Socket  to  be  user  in 
dye  houses  and  damp  places. 

mable  gases  may  exist,  both  the  socket  and  lamp 
should  be  enclosed  in  a  vapor-tight  globe  and  sup- 
ported on  a  pipe-hanger  and  wired  with  "Rubber 
Covered"  wire,  soldered  directly  to  the  circuit.  No 
fuses  or  switches  of  any  sort  should  be  used  in  the 
room  in  such  cases  as  the  slightest  arc  might  pro- 
duce dangerous  explosions  or  fires. 
102 


Splicing  should  be  done  as  described  on  page 
40,  in  fact  all  wires,  for  this  class  of  work,  should 
be  joined  in  this  thorough  manner  and  soldered. 

In  damp  or  wet  places,  such  as  dye  houses 
breweries,  etc.,  a  waterproof  socket  such  as  shown 
on  page  91,  should  be  used.  Waterproof  sockets 
should  be  hung  by  separate  stranded  rubber-cov- 
ered wires,  not  smaller  than  No.  14  (B.  &  S.). 
These  wires,  should  be  soldered  direct  to  the  circuit 
wires,  but  supported  independently  of  them.  All 
sockets  for  the  above  conditions  should  be  keyless. 

Stranded  Wires  in  every  case  should  be  sol- 
dered together  before  being  clamped  under  binding 
screws,  and  when  they  have  a  conductivity  greater 
than  No.  10  (B.  &  S.)  copper  wire,  they  should  be 
soldered  into  lugs.  Stranded  wires  if  not  thus 
stiffened  before  being  clamped  under  binding  posts 
are  liable  to  be  pressed  out  or  easily  worked  loose, 
making  a  poor  contact,  which  causes  heating,  a 
possibility  of  arcing  or  a  complete  burn  out.  Dos- 
sert  approved  solderless  lugs  may  be  used. 

Automatic  Cut-Outs  such  as  circuit  breakers 
and  fuses  should  be  placed  on  all  service  wires  as 
near  as  possible  to  the  point  where  they  enter  the 
building,  on  the  inside  of  the  walls,  and  arranged 
to  cut  off  the  entire  current  from  the  building. 

The  cut-out  or  circuit  breaker  should  always  be 
the  first  thing  that  the  service  wires  are  connected 
to  after  entering  the  building;  the  switch  next,  and 
then  the  other  fixtures  or  devices  in  their  order. 
This  arrangement  is  made  so  that  the  cut-out  or 
circuit-breaker  will  protect  all  wiring  in  the  build- 

103 


ing,  and  the  opening  of  the  switch  will  disconnect 
all  the  wiring.     (See  cuts  on  pages  33-38.) 

These  automatic  cut-outs  should  not,  however, 
be  placed  in  the  immediate  vicinity  of  easily  ignit- 
ible  stuff,  or  where  exposed  to  inflammable  gases  or 
dust,  or  to  flyings  of  combustible  material,  as  the 
arcing  produced  whenever  they  break  the  circuit 


Circuit   Breaker. 
The  New   I-T-E  Circuit  Breaker  with  Time  Limit  Feature. 

might  cause  a  fire  or  explosion.  When  they  are 
exposed  to  dampness  they  should  be  inclosed  in  a 
waterproof  box  or  mounted  on  porcelain  knobs. 
All  cut-outs  and  circuit-breakers  should  be  sup- 
ported on  bases  of  non-combustible,  non-absorptive 
insulating  material.  Link  fuses  should  never  be 
used,  they  are  obsolete  and  have  been  the  cause  of 

104 


no  end  of  fires  and  troubles.  Enclosed  fuses  are 
always  preferable. 

Cut-outs  should  operate  successfully  under  the 
most  severe  conditions  they  are  liable  to  meet  with 
in  practice,  on  short  circuits  with  fuses  rated  at  50 
per  cent,  above,  and  with  a  voltage  25  per  cent, 
above  the  current  and  voltage  for  which  they  are 
designed.  Circuit  breakers  should  also  be  designed 
to  successfully  operate  under  the  severe  conditions 
liable  to  be  met  with  in  practice,  and  when  designed 
to  carry  less  than  100  amperes  must  be  able  to  op- 
erate successfully  on  a  short  circuit  with  a  supply 
system  having  a  capacity  of  1,000  amperes.  They 
must  also  stand  2,000  volts  A.  C.  for  one  minute 
between  ground  and  live  metal  parts.  All  cut-outs 
and  circuit  breakers  should  be  plainly  marked,  and 
where  it  will  always  be  visible,  with  the  name  of 
the  maker,  and  current  and  voltage  for  which  the 
device  is  designed. 

Cut-outs  or  circuit  breakers  should  be  placed  at 
every  point  where  a  change  is  made  in  the  size  of 
wire,  unless  such  a  device  in  the  larger  wire  will 
protect  the  smaller.  They  should  never  be  placed 
in  canopies  or  shells  of  fixtures,  but  should  be  so 
placed  that  no  set  of  incandescent  lamps,  whether 
grouped  on  one  fixture  or  several  fixtures  or  pend- 
ants, requiring  more  than  660  watts  should  be  de- 
pendent upon  one  cut-out.  Special  permission  may 
be  given  in  writing  by  the  Inspection  Department 
having  jurisdiction  in  case  extra  large  or  special 
chandeliers  are  t9  be  used.  Fuses  for  cut-outs 
should  not  have  a  capacity  to  exceed  the  carrying 
capacity  of  the  wire,  and  where  circuit  breakers- 

105 


are  used  they  should  not  be  set  more  than  30  pel 
cent,  above  the  allowable  carrying  capacity  of  the 
wire,  unless  a  fusible  cut-out  is  also  installed  in  the 
circuit  as  shown  in  the  illustration  on  page  33. 
Excepting  on  main  switchboards,  or  where  they  are 
at  all  times  subject  to  expert  supervision,  circuit, 
breakers  should  never  be  used  as  a  protection  to  a 
circuit  without  the  additional  use  of  enclosed  fuse 
cut-outs. 

Circuit  breakers  open  at  exactly  the  current  they 
are  set  for  and  instantly,  therefore  it  is  necessary 
to  set  them  considerably  above  the  ordinary  amount 
of  current  required  to  keep  them  from  constantly 
opening  on  slight  fluctuations.  When  this  is  the 
case  a  double-pole  fusible  cut-out  should  be  added 
to  protect  the  wire  from  a  heavy,  steady  current, 
which  may  be  maintained  just  below  the  opening 
point  of  the  circuit  breaker.  The  fuse  requires  a 
little  time  to  heat,  and  would  not  therefore  blow 
out  with  a  momentary  rise  of  current  which  might 
open  the  circuit  breaker  if  set  as  low  as  necessary 
to  protect  the  wire,  which  may  be  of  a  size  only 
large  enough  for  the  figured  amount  of  current 
under  ordinary  conditions  of  operation.  If,  how- 
ever, in  the  case  of  motor-wiring,  the  size  of  wire 
is  25  per  cent,  above  the  figured  size  for  the  motor's 
average  current,  as  it  should  be,  then  the  intro- 
duction of  a  fusible  cut-out  in  addition  to  the  cir- 
cuit breaker  is  unnecessary,  as  is  shown  in  the 
illustration  on  page  35. 

Insulating  Joints  should  be  made  entirely  of 
material  that  will  resist  the  action  of  illuminating 
gases,  and  will  not  give  way  or  soften  under  the 


106 


heat  of  an  ordinary  gas  flame,  or  leak  under  a 
moderate  pressure  and  able  to  withstand  4,000  volts 
for  five  minutes. 

They  should  be  so  arranged  that  a  deposit  of 
moisture  will  not  destroy  the  insulating  effect,  and 
should  have  an  insulation  resistance  of  at  least 
250,000  ohms  between  the  gas  pipe  attachments, 
and  be  sufficiently  strong  to  resist  the  strain  they 
will  be  liable  to  be  subjected  to  in  being  installed. 

Insulating  joints  should  not  contain  any  soft 
rubber  in  their  composition.  The  insulating  mate- 


A    Macallen    Insulating    Joint.      B    Macallen    Canopy    and   Insulating 
Joint  in  Position.     C  Macallen  Canopy  Insulator 

.rial  should  be  of  some  hard  and  durable  material 
such  as  mica. 

Insulating  Resistance.  The  wiring  in  any  build- 
ing should  test  free  from  grounds,  i.  e.,  the  com- 
plete installation  should  have  an  insulation  between 
conductors  and  between  all  conductors  and  the 
ground  (not  including  attachments,  sockets,  recep- 
tacles, etc.)  of  not  less  than  the  following: 

Up  to       5  dinperes 4,000.000  ohms. 

10         "        2,000,000       " 

25       '  "        , 800,000       " 

107 


Up  to       50  amperes 400,000  ohms. 

100  "          200,000 

200        "       100,000 

400        "       50,000 

800        "       25,000      " 

1,600         "       and  over...    12,500 
Al   cut-outs   and  safety   devices   in   place  in  the 
above  when  the  tests  are  made. 

Where  lamp  sockets,  receptacles  and  electroliers, 
etc.,  are  connected,  one-half  of  the  above  will  be 
sufficient.  (See  page  51  for  method.) 

Knife  Switches — (Specifications).  Hinges  of 
knife  switches  should  not  be  used  to  carry  current 
unless  they  are  equipped  with  spring  washers,  held 
by  locked  nuts  or  pins  so  arranged  that  a  firm  and 
secure  connection  will  be  maintained  at  all  positions 
of  the  switch  blades  and  unless  they  are  connected 
in  circuit  so  that  the  blades  will  not  be  alive  when 
the  switch  is  open. 

The  bases  of  all  switches  should  be  made  of  non- 
combustible,  non-absorptive  insulating  material, 
such  as  slate,  marble  or  porcelain. 

Switches  for  currents  of  over  30  amperes  should 
be  equipped  with  lugs  firmly  screwed  or  bolted  to 
the  switch  and  into  which  the  conducting  wires 
should  be  soldered.  For  J:he  smaller  size  switches 
simple  screws  can  be  employed  provided  they  are 
heavy  enough  to  stand  considerable  hard  usage. 
Holes  for  inserting  screws  for  supporting  the 
switch  should  not  be  placed  between  contacts  of 
opposite  polarity. 

Pieces  carrying  the  contact  jaws  should  be  se- 
cured to  the  base  by  at  least  two  screws  or  else 

108 


rnade  with  a  square  shoulder  or  equipped  with 
dowel  pins  to  prevent  possible  turnings  and  the  nuts 
or  screw  heads  on  the  under  side  of  the  base  should 
be  countersunk  not  less  than  one-eighth  inch  and 
covered  wifli  a  waterproof  compound  which  will 
not  melt  below  150  degrees  Fahrenheit. 

All  cross-bars  less  than  three  inches  in  length 
should  be  made  of  insulating  material.  Bars  of 
three  inches  and  over  which  are  made  of  metal  to 
insure  greater  mechanical  strength  should  be  suffi- 
ciently separated  from  the  jaws  of  the  switch  to 
prevent  arcs  following  from  the  contacts  to  the  bar 
on  the  opening  of  the  switch  under  any  circum- 
stances. Metal  bars  should  preferably  be  covered 
with  insulating  material. 

All  switches  should  have  ample  metal  for  stiff- 
ness and  to  prevent  rise  in  temperature  of  any  part 
of  over  50  degrees  Fahrenheit  at  full  load,  the  con- 
tacts being  arranged  so  that  a  thoroughly  good 
bearing  at  every  point  is  obtained  with  contact  sur- 
faces advised  for  pure  copper  blades  of  about  one 
square  inch  for  each  75  amperes;  the  whole  device 
should  be  mechanicaly  well  made  throughout. 

The  following  table  shows  minimum  break  dis- 
tances and  separation  of  nearest  metal  parts  of 
opposite  polarity  for  different  voltages  and  differ- 
ent currents.  The  values  given  are  correct  for 
switches  to  be  used  on  direct  cuirent  systems  and 
can  therefore  be  safely  followed  in  devices  designed 
for  alternating  currents. 

All  switches  should  be  plainly  marked,  where  it 
can  be  read,  when  the  switch  is  installed,  with  the 
name  of  the  maker  and.  the  current  and  voltage  for 
which  the  switch  is  designed. 

109 


KNIFE    SWITCH    DIMENSIONS 

Minimum  Separation  of         Minimum 
Nearest  Metal  Parts  of  Break- 

Opposite  Palarity.  Distance. 

125  VOLTS  OR  LESS: 

For  Switchboards  and  Panel 
Boards: — 

10  amperes  or  less H  inch y2  inch. 

11-30    amperes 1          '     H     ' 

60  " 1J4     "     1 

For  Individual  Switches: — 

30  amperes 1 1A  inch 1       inch. 

60-100       "        ll/2     "     1J4     " 

200-300       "        2%     "     2 

400-600       "        2}4     "     2*/2     ' 

800-1000     "        3          "     2&     " 


250    VOLTS    D.    C,    AND    NOT 

OVER  500  VOLTS  A.  C: 
For  all  Switches:— 

31-100  amperes 2J4  inch 2       inch. 

200-300          "        2y2  "    2J4     " 

400-600          "        2^  "     2J4     " 

800-1000        "        3  "     2J4     " 

A  300-ampere  switch  with  the  spacings  of  the  200-ampere  switch 
above  may  be  used  on  switchboards. 

Cut  out  terminals  on  switches  for  over  250  volts  must  be  designed 
and  spaced  for  600-volt  fuses. 

600  VOLTS : 

For  all  Switches: — 

30-60  amperes 4       inch 3l/2  inch. 

100        "        4J4     "     4 

Auxiliary  contacts  of  either  a  readily  renewable 
or  a  quick-break  type  or  the  equivalent  are  recom- 
mended for  D.  C.  switches,  designed  for  over  250 
volts,  and  should  be  provided  on  D.  C.  switches  de- 
signed for  use  in  breaking  currents  greater  than  100 
amperes  at  a  voltage  of  over  250. 

For  3-wire  direct  current  and  3-wire  single  phase 
systems  the  separation  and  break  distances  for  plain 
3-pole  knife  switches  should  not  be  less  than  those 
required  in  the  above  table  for  switches  designed 

for  the  voltage  between  neutral  and  outside  wires, 
no 


Knife  Switches  (Installation).  Switches  should 
be  placed  on  all  service  wires,  either  overhead -or 
underground,  in  the  nearest  readily  accessible 
place  to  the  point  where  the  wires  enter  the  build- 
ing, and  arranged  to  cut  off  the  entire  current. 

Service  cut-out  and  switch  should  be  arranged  to 
cut  off  current  from  all  devices  including  meters. 

In  risks  having  private  plants  the  yard  wires 
running  from  building  to  building  are  not  consid- 
ered as  service  wires,  so  that  switches  would  not 
be  required  in  each  building  if  there  are  other 
switches  conveniently  located  on  the  mains  or  if 
the  generators  are  near  at  hand. 

Switches  should  always  be  placed  in  dry,  acces- 
sible places,  and  be  grouped  as  far  as  possible. 
Single-throw  knife  switches  should  be  so  placed 
that  gravity  will  not  tend  to  close  them.  Double- 
throw  knife  switches  may  be  mounted  so  that  the 
throw  will  be  either  vertical  or  horizontal  as  pre- 
ferred, but  if  the  throw  be  vertical  a  locking  device 
should  be  provided,  so  constructed  as  to  insure  the 
blades  remaining  in  the  open  position  when  so  set. 

When  practicable  switches  should  be  so  wired 
that  blades  will  be  "dead"  when  switch  is  open. 

When  switches  are  used  in  rooms  where  com- 
bustible flyings  would  be  likely  to  accumulate 
around  thefn,  they  should  be  enclosed  in  dust-tight 
cabinets. 

Up  to  250  volts  and  thirty  amperes,  approved  in- 
dicating snap  switches  are  suggested  in  preference 
to  knife  switches  on  lighting  circuits. 

Single  pole   switches   should   never  be   used   as 

service  switches  nor   for  the  control   of   outdoor 
111 


signs  or  circuits  located  in  damp  places,  nor  placed 
in  the  neutral  wire  of  a  three-wire  system,  except 
in  the  two-wire  branch  or  tap  circuit  supplying  not 
more  than  660  watts. 

Three-way  switches  are  considered  as  single  pole 
switches. 

Where  flush  switches  or  receptacles  are  used, 
whether  with  conduit  systems  or  not,  they  should 


An    Approved   Double   Pole   Knife    Switch,    Showing   Terminals    for 

Approved  Enclosed  Fuses.     Always  install  so  that  the 

handle  will  be  up  when  circuit  is  closed. 


be  enclosed  in  an  approved  box  constructed  of  iron 
or  steel,  in  addition  to  the  porcelain  enclosure  of 
the  switch  or  receptacle.  Where  in  floor  outlets 
attachment  plugs  are  liable  to  mechanical  injury,  or 
the  presence  of  moisture  is  probable,  floor  outlet 
boxes  especially  designed  for  this  purpose  should 
be  used. 

Where  possible,  at  all  switch  or  fixture  outlets, 

118 


unless  outlet  boxes  which  will  give  proper  support 
for  fixtures  are  used,  a  seven-eighths  inch  block 
should  be  fastened  between  studs  or  floor  timbers 
flush  with  the  back  of  lathing  to  hold  tubing,  and 
to  support  switches  or  fixtures.  When  this  cannot 
be  done,  wooden  base  blocks,  not  less  than  three- 
fourths  inch  in  thickness,  securely  screwed  to  lath- 
ing, or  approved  fittings  or  plates -designed  for  the 
service,  should  be  provided  for  switches,  and  also 
for  fixtures  which  are  not  attached  to  gas  pipes  or 
conduit. 

Sub-bases  of  non-combustible,  non-absorptive, 
insulating  material,  which  will  separate  the  wires 
at  least  one-half  inch  from  the  surface  wired  over, 
should  be  installed  under  all  snap  switches  used  in 
exposed  knob  and  cleat  work.  Sub-bases  should 
also  be  used  in  moulding  work,  but  they  may  be 
made  of  hardwood  or  they  may  be  omitted  if  the 
switch  is  approved  for  mounting  directly  on  the 
moulding. 

Flush  Switches.  Where  gangs  of  flush 
switches  are  used,  whether  with  conduit  systems  or 
not,  the  switches  should  be  enclosed  in  boxes  con- 
structed of,  or  lined  with,  fire-resisting  material. 

Where  two  or  more  switches  are  placed  under 
one  plate,  the  box  should  have  a  separate  compart- 
ment for  each  switch.  No  push  buttons  for  bells, 
gas-lighting  circuits,  or  the  like,  should  be  placed 
in  the  same  wall  plate  with  switches  controlling 
electric  .light  or  power  wiring. 

Snap  Switches  like  knife  switches,  should  al- 
ways be  mounted  on  non-combustible,  non-absorp- 
tive insulating  bases,  such  as  slate  or  porcelain,  and 

118 


should  have  carrying  capacity  sufficient  to  prevent 
undue  heating. 

When  used  for  service  switches  they  should  in- 
dicate at  sight  whether  the  current  be  "on"  or  "off." 
Indicating  switches  should  be  used  for  all  work  to 
prevent  mistakes  and  possible  accidents.  The  fact 
that  lights  do  not  burn  or  the  motor  does  not  run 
is  not  necessarily  a  sure  sign  that  the  current  is  off. 

Every  switch,  like  every  other  piece  of  electrical 
apparatus,  should  be  plainly  marked  where  it  is 
always  visible  with  the  maker's  name  and  the  cur- 
rent and  voltage  for  which  it  is  designed. 

On  constant  potential  systems,  these  switches, 
like  knife  switches,  should  operate  successfully  at 
50  per  cent,  overload  in  amperes  with  25  per  cent, 
excessive  voltage  under  the  most  severe  conditions 
they  are  likely  to  meet  with  in  practice.  They 
should  have  a  firm  contact,  should  make  and  break 
readily,  and  not  "stop  when  motion  has  once  been 
imparted  to  the  handle. 

On  constant  current  systems,  they  should  close 
the  main  circuit  and  disconnect  the  branch  wires 
when  turned  "off";  should  be  so  constructed  that 
they  will  be  automatic  in  action,  not  stopping  be- 
tween points  when  started  and  should  prevent  an 
arc  between  the  points  under  all  circumstances. 


LAMP    DATA 

The  illumination  given  by  one  candle  at  a  dis- 
tance of  one  foot  is  called  the  "candle  foot,"  and 
is  taken  as  a  unit  of  intensity.  In  general,  inten- 
sity of  illumination  should  nowhere  be  less  than 
one  candle-foot,  and  the  demand  for  light  at  the- 

114 


INCANDESCENT  LAMP  DATA 

CARBON   I.AMPS 


Volts 

Watts 

C.  P. 

W.  P.  C. 

Amps. 

Hot  Res 

110 

10 
20 
30 
50 
60 

2-0 

4.8 
9.3 
16.8 
20-2 

5.00 
4-15 
3.23 
2.97 
2.97 

0.191 
0-182 
0.273 
0.455 
0.546 

1210.00 
605.00 
403.00 
242.00 
201  .80 

220 

30      - 
35 
60 

5.1 
8.0 
16.3 

5.90 
4-40 
3-69 

0.  1363 
0.159 
0-273 

1613.3 
1382.00 
806-00 

GEM  LAMPS   (METALLIC  FILAMENT) 


Volts 

Watts 

C.  P. 

W.  P.  C. 

Amps. 

Hot  Res. 

110 

20 
30 
40 
50 
60 
80 
100 

5.0 
10.0 
156 
20.0 
24.0 
325 
40.7 

4.00 
3.00 
2.56 
2.50 
2.50 
2.46 
2.46 

0.1818 
0.273 
0.364 
0.455 
0.546 
1.727 
1.909 

605.0 
403.3 
302.0 
242.0 
201.5 
151.4 
121.0 

MAZDA    (VACUUM)    LAMPS 


Volts 

Watts 

C.  P. 

W.  P.  C. 

Amps. 

Hot  Res. 

110 

10 

7.7 

1.30 

0.0909 

1210.0 

15 

13.0 

1.15 

0.1363 

807.0 

20 

18.2 

1.10 

01818 

605.0 

" 

25 

23.8 

1.05 

0.227 

484.0 

•• 

40 

38.8 

1.03 

0.364 

302.5 

60 

60.0 

1.00 

0.546 

201.7 

«• 

100 

105.0 

.95 

0.909 

121.0 

150 

167*.0 

.90 

1.363 

80.7 

" 

250 

278.0 

.90 

2.272 

48.4 

" 

400 

444.0 

.90 

3.640 

30.2 

" 

500 

556.0 

.90 

4.550 

24.2 

MAZDA    (TYPE    C)    LAMPS    (GAS    FILLED) 


Volts 

Watts 

C.  P. 

W.  P.  C. 

Amps. 

Hot  Res. 

110 

200 
300 
400 
500 
750 
1000 

250.0 
385.0 
533.0 
714.0 
1250.0 
1820.0 

0.80 
0.78 
0.75 
0.70 
0.60 
0.55 

1.82 
2.73 
3.64 
4.55 
6.82 
9.09 

60.5 
40.3 
30.3 
24.2 
16.1 
12.1 

220 

25 
40 
60 
100 
150 
250 
500 

19.2 
33.3 
50.0 
90.9 
143.0 
250.0 
556.0 

130 
1.20 
1.20 
1.10 
.  1.05 
1.00 
1.00 

0.1136 
0.1818 
0.273 
0.455 
0.682 
1.136 
2.273 

1936.0 
1210.0 
807.0 
484.0 
322.0 
193.6 
96.7 

115 


The  tables  below  show  the  variation  in  the  life  and  candle-power 
of  incandescent  lamps  with  various  percentages  of  decrease  and 
increase -of  rated  voltages 

CARBON    FILAMENT   LAMP   VARIATIONS. 


% 

Volts 

% 
C.  P. 

% 
Amperes 

% 
Ohms 

% 
Watts 

% 
W.  P.C. 

% 
Ufe 

10 

69.8 

10.8 

21.9 

28.2 

85.5 

9 

61.4 

9.7 

19.5 

25.9 

82.6 

8 

534 

8.5 

172 

23.5 

79.0 

<o 

«u  45.6 

„     7.5 

c  15.0 

v  21.0 

v    74.6 

\ 

S  38.2 

%     6.4 

3  12.8 

3  18.4 

S    69.3 

fi 

£  31.1 

£     5.4 

.,_, 

£  10.6 

S  15.7 

£    62.7 

J     • 

w  24.3 
S  17.9 

S     4-2 
S     3.2 

a 
a 

(A 

o    8-4 
S     6.3 

£  12.8 
P     9.8 

g    54.8 
Q    45.1 

11.6 

2.1 

4.2 

6.7 

33.1 

5.7 

1.2 

5 

2.1 

3.4 

18.5 

Normal 

0 

0 

j>> 

0 

0 

0 

1 

5.4 

1.2 

jB 

2.1 

3.6 

22.5 

2 

10.6 

2.1 

**3 

4.1 

7.3 

50.5 

3 

15.5 

3.2 

a 

6.1 

11.2 

85.3 

%       4 

g  *03 

%     4'2 

£ 

%     8-l 

o  15.3 

v  1289 

8      5 

S  24.8 

«     5.4 

3  10.1 

«  19.6 

<§  180.0 

b       6 

g  29  o: 

S     6.4 

£  12.0 

£  24.1 

£  250.4 

«       8 

8  33.2 
O  37.1 

£     7.4 

0    8.4 

£  13.9 
Q  158 

o  28.8 
S  33.8 

§  336.0 
5  442.0 

9 

40.7 

9.5 

17.7 

39.0 

578.0 

10 

44.3 

10.7 

19.6 

44.4 

747.0 

METAL   FILAMENT   LAMP   VARIATIONS. 


%  Change 
in 
Voltage 

%  C.  P. 

Mazda 
[Vacuum) 

%  Watts 
Mazda 
(Vacuum) 

%  C.  P. 
Mazda 
(Type  C.) 

%  Watts 
Mazda 
(Type  C.) 

%  C.  P. 
Gem 

%  Watts 
Gem 

10 

39.7 

16.3 

36.3 

15.9 

58.0 

18.4 

9 

35.3 

14.6 

32.3 

14.3 

51.3 

16.5 

8 

31.0 

12.9 

28.4 

12.7 

44.7 

14.6 

7 

v  26.8 

4>    11.3 

a,    24.6 

<u     11.2 

v  38.4 

<u  12.7 

«g       6 

S  22.7 

S     9.6 

3   20-8 

S      9.5 

Jg  32.3 

3  10.8 

8      5 

£  18-7 

£     8.0 

2     17.2 

£      7.9 

£  26.4 

£    9-0 

y              4 

"  14.8 

o     6.4 

b     13.6 

«      6.2 

o  20.7 

£      3 

5  10.9 

5     4.8 

«     10.1 

S      4.7 

fl  15.2 

O       e'x 

2 

7.2 

3.2 

6.6 

3.1 

10.0 

3^6 

1 

3.6 

1.6 

3.3 

1.6 

4.9 

1.8 

Normal 

0 

0 

0 

0 

0 

0 

I 

3.5 
7.0 
10.3 

1.6 
3.3 
4.6 

3.3 

6.4 

1.6 
3.0 

A  A 

4.7 
9.3 
13.6 

1.8 

3.6 

J>          A 

S      5 
I      7 

<u  13.4 
S  16.4 
£  19.6 
8  22.5 
Q  25.4 
28.2 
30.9 

f     6.2 
3     7.8 
£    9.4 
S  11.0 
Q  12.4 
14.0 
15.3 

2     15^5 
b     18.2 
£    21.0 
Q    23.8 
26.4 
29.0 

4.O 

%      6.0 
2      6.5 

b    9.0 

%     10.4 
Q     12.0 
13.3 
15.0 

V  17-8 
3  21.8 
£  25.7 
8  29.4 
Q  33.0 
36.4 
39.7 

I    " 
S    8.7 
fc  10.4 

o  12-1 
fi  13.8 
15.5 
17.1 

110 


COOPER  HBWlTr  LAMP  UNITS-DIRECT  CURRENT 


Type 

Watts 

Length  of 
tubes,  ins. 

Candle 
power 

Watts 

per  candle 

H                           

192 

21" 

300 

.64 

Double  H  

385 

2-21"  'ea. 

600 

.64 

K                      

385 

45" 

700 

.55 

P 

385 

50'' 

800 

.48 

ALTERNATING  CURRENT  (60-cycle,  95-125  volts) 


F 


400 


50" 


800 


.50 


Power   Factor   70%. 


COOPER  HEWITT  QUARTZ  LAMP— DIRECT  CURRENT 


Y  tor  110  volts 
Z    "     220    " 


418 
725 


1000 
2400 


.40 
.30 


present  time  quite  frequently  raises  the  brilliancy 
to  double  this  amount.  The  intensity  of  light 
varies  inversely  with  the  square  of  the  distance.  A 
i6-candle-power  lamp  gives  a  candle-foot  of  light 
as  a  distance  of  four  feet.  A  candle-foot  of  light 
is  a  good  intensity  for  reading  purposes. 

Assuming  the  i6-candle-power  lamp  as  the  stand- 
ard, it  is  generally  found  that  two  i6-candle-power 
lamps  per  100  square  feet  of  floor  space  gives  good 
illumination,  three  very  bright,  and  four  brilliant. 
These  general  figures  will  be  modified  by  the  height 
of  ceiling,  color  of  walls  and  ceiling,  and  other  local 
conditions.  The  lighting  effect  is  reduced,  of 
course,  by  an  increased  height  of  ceiling.  A  room 
with  dark  walls  requires  nearly  three  times  as  many 
lights  for  the  same  illumination  as  a  room  with 
walls  painted  white.  With  the  amount  of  intense 
light  available  in  arc  and  incandescent  lighting,  there 
is  danger  of  exceeding  "the  limits  of  effective  illum- 

117 


ination  and  producing  a  glaring  intensity,"  which 
should  be  avoided  as  carefully  as  too  little,  intensity 
of  illumination. 

Distribution  considers  the  arrangement  of  the 
various  sources  of  light  and  the  determination  of 
their  candle-power.  The  object  should  be  to  "se- 
cure a  uniform  brilliancy  on  a  certain  plane,  or 
within  a  given  space.  A  room  uniformly  lighted, 
even  though  comparatively  dim,  gives  an  effect  of 
much  better  illumination  than  where  there  is  great 
brilliancy  at  some  points  and  comparative  darkness 
at  others.  The  darker  parts,  even  though  actually- 
light  enough,  appear  dark  by  contrast,  while  the 
lighter  parts  are  dazzling.  For  this  reason  naked 
lights  of  any  kind  are  to  be  avoided,  since  they 
must  appear  as  dazzling  points,  in  contrast  with 
the  general  illumination." 

The  arrangement  of  the  lamps  is  dependent 
very  largely  upon  existing  conditions.  In  factories 
and  shops,  lamps  should  be  placed  over  each  ma- 
chine or  bench  so  as  to  give  the  necessary  light  for 
each  workman.  In  the  lighting  of  halls,  public 
buildings  and  large  rooms,  excellent  effects  are  ob- 
tained by  dividing  the  ceilings  into  squares  and 
placing  a  lamp  in  the  center  of  each  square.  The 
size  of  square  depends  on  the  height  of  ceiling 
and  the  intensity  of  illumination  desired.  Another 
excellent  method  consists  in  placing  the  lamps  in 
a  border  along  the  walls  near  the  ceiling. 

For  the  illumination  of  show  windows  and  dis- 
play effects,  care  must  be  taken  to  illuminate  by 
reflected  light.  The  lamps  should  be  so  placed  as 
us 


to  throw  their  rays  upon  the  display  without  casting 
any  direct  rays  on  the  observer. 

The  relative  value  of  high  candle-power  lamps 
in  place  of  an  equivalent  number  of  i6-candle-power 
lamps  is  worthy  of  notice.  Large  lamps  can  be 
efficiently  used  for  lighting  large  areas,  but  in  gen- 
eral, a  given  area  will  be  much  less  effectively  light- 
ed by  high  candle-power  lamps  than  by  an  equiva- 
lent number  of  lo-candle-power  lamps.  For  exam- 
ple, sixteen  64-candle-power  lamps  distributed  over 
a  large  area  wrill  not  give  as  good  general  illumina- 
tion as  sixty-four  i6-candle-power  lamps  distribut- 
ed over  the  same  area.  High  candle-power  lamps 
are  chiefly  useful  when  a  brilliant  light  is  needed  at 
one  point,  or  where  space  is  limited  and  an  increase 
in  illuminating  effect  is  desired. 

The  relative  value  of  the  arc  and  incandescent 
systems  of  lighting  is  frequently  difficult  to  deter- 
mine. Incandescent  lamps  have  the  advantage  that 
they  can  be  distributed  so  as  to  avoid  the  shadows 
necessarily  cast  by  one  single  source  of  light.  Arc 
lamps  used  indoors  with  ground  or  opal  globes  cut- 
ting off  half  the  light,  have  an  efficiency  not  great- 
er than  two  or  three  times  that  of  an  incandescent 
lamp.  Nine  5O-watt,  i6-candle-power  lamps  con- 
sume the  same  power  as  one  full  45O-watt  arc  lamp. 
It  has  been  found  that  unless  an  area  is  so  large  as 
to  require  200  or  300  incandescent  lights  distributed 
over  it,  arc  lamps  requiring  total  power  will  not 
light  the  area  with  as  uniform  brilliancy. 

Cut-Outs,  other  than  rosettes  aijd  attachment 
plugs,  are  of  two  classes:  The  link-fuse  cut-out 


119 


and  the  enclosed-f use  cut-out.  In  both  cases  they 
should  be  supported  on  bases  of  non-combustible, 
non-absorptive  insulation  material. 

All  cut-outs  should  be  of  the  enclosed  type,  when 
not  arranged  in  approved  cabinets,  so  as  to  obviate 
any  danger  of  the  melted  fuse  metal  coming  in 
contact  with  any  substance  which  might  be  ignited 
thereby. 

Cut-outs  must  operate  successfully  on  short  cir- 
cuits, under  the  most  severe  ^conditions  with  which 
they  are  liable  to  meet  in  practice,  at  25  per  cent, 
above  their  rated  voltage,  and  for  link-fuse  cut- 
outs with  fuses  rated  at  50  per  cent,  above  the  cur- 
rent for  which  the  cut-out  is  designed,  and  for  en- 
closed-fuse  cut-outs  with  the  largest  fuses  for  which 
the  cut-out  is  designed. 

With  link-fuse  cut-outs  there  is  always  the  pos- 
sibility of  a  larger  fuse  being  put  into  the  cut-out 
than  it  was  designed  for,  which  is  not  true  of  en- 
closed-fuse  cut-outs. 

The  most  severe  service  which  can  be  required 
of  a  cut-out  in  practice  is  to  open  a  "dead  short- 
circuit,"  with  only  one  fuse  blowing,  and  it  is  with 
these  conditions  that  all  tests  should  be  made. 

Cut-outs  should  be  marked  where  it  will  be 
plainly  visible  when  installed  with  the  name  of  the 
maker,  and  current  and  voltage  for  which  the  de- 
vice is  designed. 

LINK-FUSE  CUT-OUTS. 

Should   be  mounted   on   bases  made  of   strong, 
120 


non-combustible,  non-absorptive,  insulating  •  mate- 
rial. The  design  of  the  base  should  be  such  that, 
considering  the  material  used,  the  base  will  with- 
stand the  most  severe  conditions  liable  to  be  met 
in  practice.  Bases  with  an  area  of  over  twenty- 
five  square  inches  should  have  at  least  four  support- 
ing screws.  Holes  for  supporting  screws  should 
be  kept  outside  of  the  area  included  by  the  outside 
edges  of  the  fuse-block  terminals,  and  should  be 
so  located  or  countersunk  that  there  will  be  at  least 
one-half  of  an  inch  space,  measured  over  the  sur- 
face, between  the  head  of  the  screw  or  washer  and 
the  nearest  live  metal  part. 

Nuts  or  screw  heads  on  the  under  side  of  the 
base  should  be  countersunk  not  less  than  one-eighth 
inch,  and  covered  with  a  waterproof  compound. 

All  fuse-block  terminals  should  have  ample  metal 
for  stiffness  and  to  prevent  rise  in  temperature  of 
any  part  of  over  50  degrees  Fahr.  (28  degrees  Cen.) 
at  full  load.  Terminals,  as  far  as  practicable, 
should  be  made  of  compact  form  instead  of  being 
rolled  out  in  thin  strips;  and  sharp  edges  or  thin 
projecting  pieces,  as  on  wing  thumb  nuts  and  the 
like,  should  be  avoided.  Thin  metal,  sharp  edges 
and  projecting  pieces  are  much  more  likely  to  cause 
an  arc  to  start  than  a  more  solid  mass  of  metal. 

Clamps  for  connecting  the  wires  to  the  fuse- 
block  terminals  should  be  of  solid,  rugged  construc- 
tion, so  as  to  insure  a  thoroughly  good  connection 
and  to  withstand  considerable  hard  usage.  For 
fuses  rated  at  over  30  amperes,  lugs  firmly  screwed 
or  bolted  to  the  terminals  and  into  which  the  con- 
ducting wires  are  soldered  should  be  used. 

121 


Spacings  should  be  at  least  as  great  as  those  given 
in  the  following  table : 

Separation  ofnearest 

OPEN    LINK    FUSES  metal  parts  of  Minimum 

125    VOLTS    OR    LESS.  opposite  polarity.  break  distance. 

10    amperes    or    less 54  inch 54  inch. 

11 — 100  amperes   1 

101—300  "  ..1 


UP    TO    250    VOLTS. 

10    amperes    or    less 


11  —  100  amperes 


•  IK 


101—300 

A  space  should  be  maintained  between  fuse  ter- 
minals of  the  same  polarity  of  at  least  one-half  inch 
for  voltages  up  to  125,  and  of  at  least  three-quarter 
inch  for  voltages  from  126  to  250.  This  is  the 
minimum  distance  allowable,  and  greater  separa- 
tion should  be  provided  when  practicable. 

For  250  volt  boards  or  blocks  with  the  ordinary 
front-connected  terminals,  except  where  these  have 
a  mass  of  compact  form,  equivalent  to  the  back- 
connected  terminals  usually  found  in  switchboard 
work,  a  substantial  barrier  is  insulating  material, 
not  less  than  one-eighth  of  an  inch  in  thickness, 
should  be  placed  in  the  "break"  gap — this  barrier 
to  extend  out  from  the  base  at  least  one-eighth  of 
an  inch  farther  than  any  bare  live  part  of  the  fuse- 
block  terminal,  including  binding  screws,  nuts  and 
the  like. 

For  three-wire  systems  cut-outs  should  have  the 
break-distance  required  for  circuits  of  the  potential 
of  the  outside  wires. 

ENCLOSED-FUSE  CUT-OUTS— PLUG  AND 
CARTRIDGE  TYPE. 

The  bases  should  be  made  of  non-combustible, 
122 


non-absorptive,  insulating  material.  Blocks  with  an 
area  of  over  twenty-five  square  inches  should  have 
at  least  four  supporting  screws.  Holes  for  support- 
ing screws  must  be  so  located  or  countersunk  that 
there  will  be  at  least  one-half  of  an  inch  space, 
measured  over  the  surface,  between  the  screw-head 
or  washer  and  the  nearest  live  metal  part,  and  in  all 
cases  when  between  parts  of  opposite  polarity 
should  be  countersunk. 

Nuts  or  screw-heads  on  the  under  side  of  the 
base  should  be  countersunk  at  least  one-eighth  of 
an  inch  and  covered  with  a  waterproof  compound. 

Except  for  scalable  service  and  meter  cut-outs, 
terminals  should  be  of  either  the  Edison  plug,  spring 
clip  or  knife-blade  type,  of  approved  design,  to 
take  the  corresponding  standard  enclosed  fuses. 
They  should  be  secured  to  the  base  by  two  screws  or 
the  equivalent,  so  as  to  prevent  them  from  turn- 
ing, and  must  be  so  made  as  to  secure  a  thoroughly 
good  contact  with  the  fuse.  End  stops  should  be 
provided  to  insure  the  proper  location  of  the  car- 
tridge fuse  in  the  cut-out. 

Clamps  for  connecting  wires  to  the  terminals 
should  be  of  a  design  which  will  insure  a  thor- 
oughly good  connection  and  should  be  sufficiently 
strong  and  heavy  to  withstand  considerable  hard 
usage.  For  fuses  rated  to  carry  over  thirty  am- 
peres, lugs  firmly  screwed  or  bolted  to  the  terminals 
and  into  which  the  connecting  wires  shall  be  sold- 
ered should  be  used. 

They  should  be  classified  as  regards  both  cur- 
rent and  voltage. 

123 


ENCLOSED   FUSES    (CARTRIDGE  TYPE). 

Fuses  of  this  type  for  light,  power  and  heating 
circuits  should  have  their  fusible  strips,  or  wire, 
permanently  attached  to  their  terminals  within  the 
cartridge  so  as  to  obtain  a  thoroughly  good  con- 
nection and  make  it  impossible  to  replace,  by  the 
user,  when  melted  by  an  overload  or  short  circuit. 

No  enclosed  fuses  should  ever  be  used  which  do 
not  bear  the  name,  or  trade-mark  of  the  maker,  and 
the  words  "National  Electrical  Code  Standard,"  or 
its  abbreviation,  "N.  E.  Code  Std.,"  or  "N.  E.  C.  S." 

No  enclosed  fuses  should  ever  be  refilled  by  the 
user  but  should  be  returned  to  their  makers,  who 
will  refill  them  at  a  nominal  cost. 

There  are  no  "Renewable"  or  "Refillable"  en- 
closed or  cartridge  fuses,  so-called,  approved  by  the 
National  Board  of  Fire  Underwriters,  or  appear  in 
the  list  of  Electrical  Fittings  published  by  the  Na- 
tional Board  of  Fire  Underwriters. 

Following  is  the  list  of  makers  of  approved  en- 
closed or  cartridge  fuses:  Bryant  Electric  Co.. 
"Bryant";  Chase-Shawmut  Co.,  "Shawmut"  (Con- 
dit  Electrical  Mfg.  Co.,  sole  agents)  ;  Chicago  Fuse 
Mfg.  Co.,  "Union";  Detroit  Fuse  &  Mfg..  Co., 
"Arkless";  D.  &  W.  Fuse  Co.,  "D.  &  VV."; 
General  Electric  Co.,  "G.  E.";  Johns-Pratt  Co., 
"Noark"  (H.  W.  Johns-Manville  Co.,  sole  agents)  ; 
Westinghouse  Elec.  &  Mfg.  Co.,  "Westinghouse." 

For  dimensions  of  National  Electrical  Code 
Standard  fuses  see  two  following  pages. 

124 


Table  of  Dimensions  of  the 
Standard  Cartridge 


f 

u  •  — 


nMiNAU   FOK 
O- 6O    AMPERES 


Form  1.    CARTRIDGE  FUSE-Ferrule  Contact. 


Voltage. 

Rated 
Capacity. 

Amperes  . 

A 

B 

C 

Width 
of 
Contact 
Clips. 
Inches. 

Length 
over 
Terminals. 

Inches. 

Distance 
between 
Contact 
Clips. 
Inches. 

0-250 

0-30 
31-60 

I         3 

i 

if 

i 

61-100 

IOI-2OO 

201-400 
401-600 

~          51 
I        jj 

4 

5 
6 

if 

251-600 

0-30 
31-60 

I         I* 

.      4i 

f 

61-100 

IOI-2OO 

201-400 

71 
E         9f 
•£       n| 

6 

7 
8 

1 

125 


National  Electrical  Code 
Enclosed  Fuse. 


Form  2.    CARTRIDGE  FUSE— Knife  Blade  Contact. 


D 

E 

F 

G 

Rated 
Capacity. 

Amperes 

Dia.  of  Ferrules 
or  Thickness 
of  Terminal 
j  Blades. 
Inches. 

Min.  Length  of 
Ferrules  or  of 
Terminal  Blades 
Outside  of  Tube. 
Inches. 

Dia. 
of 

Tube. 

Inches. 

Width  of 
Terminal 
Blades. 

Inches. 

A 

tt 

f 

f 

i 

0-30 
31-60 

H 

i 

i 
if 

2i 

i 

2 

2 

61-100 

101-200 

201-400 
401-600 

# 

1 
f 

I 

| 

0-30 
31-60 

i 

I 
'f 

If 

8     (>| 

ri    S 

i*2 

61-100 

IOI-2OO 

201-400 

126 


CURRENT       REQUIRED       TO       FUSE 

WIRES    OF   COPPER,    GERMAN 

SILVER  AND  IRON. 


B.  &S. 
Gauge. 

10 

11 

12 

13 

14 

15 

16 

17 

18 

19 

20 

21 

22 

23 

24 

25 

26 

27 

28 

2P 

30 

31 

32 

33 

34 

35 

36 

37 

38 

39 

40 


German 

Copper, 

Silver, 

Iron, 

Amperes. 

Amperes. 

Amperes. 

333. 

169. 

101. 

284. 

146. 

86. 

235. 

120.7 

71.2 

200. 

102.6 

63. 

166. 

85.2 

50.8 

139. 

71.2 

42.1 

117. 

60. 

35.5 

99. 

50.4 

32.6 

82.8 

*2.5 

25.1 

66.7 

34.2 

20.2 

58.3 

29.9 

17.7 

49.3 

25.3 

14.9 

41.2 

21.  1 

12.5 

34.5 

17.7 

10.9 

28.9 

14.8 

8.76 

24.6 

12.6 

7.46 

20.6 

10.6 

6.22 

17.7 

9.1 

5.36 

14.7 

7.6 

4.45 

12.5 

6.41 

3.79 

30.25 

5.26 

3.11 

8.75 

4.49 

2.65 

7.26 

3.73 

2.2 

6.19 

3.18 

1.88 

5.12 

2.64 

1.55 

4.37 

t.24 

1.33 

3.62 

1.86 

1.09 

3.08 

1.58 

.93 

2.55 

1.31 

.77 

2.20 

1.13 

.67 

1.86 

.95 

.56 

The  above  cut  illustrates  the  manner  in  which  harder 
metal  tips  should  be  attached  to   fuse   wire. 


127 


LINK  FUSES. 

Should  have  contact  surfaces  or  tips  of  harder 
metal,  having  perfect  electrical  connections  with 
the  fusible  part  of  the  strip. 

The  use  of  the  hard  metal  tip  is  to  afford  a  strong 
mechanical  bearing  for  the  screws,  clamps,  or  other 
devices  provided  for  holding  the  fuse. 

They  should  be  stamped  with  about  80  per  cent, 
of  the  maximum  current  which  they  can  carry  in- 
definitely, thus  allowing  about  25  per  cent,  overload 
before  the  fuse  melts. 

With  naked  open  fuses,  of  ordinary  shapes  and 
with  not  over  500  amperes  capacity,  the  minimum 
current  which  will  melt  them  in  about  five  minutes 
may  be  safely  taken  as  the  melting  point,  as  the 
fuse  practically  reaches  its  maximum  temperature 
in  this  time.  With  larger  fuses  a  longer  time  is 
necessary. 

Fuse  terminals  should  be  stamped  with  the  mak- 
er's name  or  initials,  or  with  some  known  trade- 
mark. 

Cabinets.  Should  in  all  cases  be  made  amply 
strong  and  rigid  to  keep  their  shape,  permitting 
their  doors  to  close  tightly,  and  making  it  possible 
to  install  the  wiring  and  conduit  properly.  Cabi- 
nets may  be  constructed  of  cast  or  sheet  metal, 
wood  or  approved  composition.  Wood  or  com- 
position cabinets  should  not  be  used  when  con- 
nected with  metal  conduit,  metal  moulding,  or 
armored  cable  systems. 

All  metal  cabinets  should  be  thoroughly  painted 
or  treated  to  prevent  rust  or  corosion. 

128 


Wooden  Cabinets.  Wood  should  be  well  sea- 
soned and  at  least  three-fourths  inch  thick,  and 
be  thoroughly  filled  and  painted,  and  should  be 
lined  with  a  non-combustible  material. 

In  all  cabinets,  linings  of  slate,  marble  or  ap- 
proved composition  should  be  at  least  one-fourth 
inch  thick  and  firmly  secured  in  place;  when  metal 
is  used  for  the  lining  it  should  be  at  least  No.  16 
U.  S.  gage  in  thickness.  For  lining  wooden  cabi- 
nets one-eighth  inch  rigid  asbestos  board  may  be 
used  when  firmly  secured  in  place  by  screws  or 
tacks. 

Metal  Cabinets.  If  cast  metal  is  used  a  thick- 
ness of  at  least  one-eighth  inch  should  be  provided. 
Sheet  metal  should  not  be  less  than  .0625  inch  thick 
(No.  1 6  U.  S.  gage).  In  steel  cabinets  having  an 
area  of  more  than  360  square  inches  for  any  sur- 
face, or  having  a  single  dimension  greater  than  2 
feet,  sheet  metal  should  be  used  at  least  No.  14 
U.  S.  gage  in  thickness;  in  those  having  an  area 
of  more  than  1,200  square  inches  for  any  surface, 
or  having  a  single  dimension  greater  than  4^-2  feet, 
the  sheet  metal  should  be  at  least  No.  12  U.  S.  gage 
in  thickness. 

Doors  should  shut  closely  at  all  edges  against  a 
rabbet  formed  as  a  part  of  the  door  or  trim  or 
have  turned  flanges  at  all  edges.  Hinges  should  be 
of  strong  and  durable  design.  A  substantial  Jatch 
or  catch  should  be  provided  so  as  to  keep  the  door 
closed,  and  a  lock  may  be  used  in  addition  to  the 
catch  if  desired. 

When  doors  have  glass  panels  the  glass  should 

129 


be  at  least  one-eighth  inch  thick  (commercial  thick- 
ness), and  should  not  have  a  greater  area  than  450 
square  inches  unless  plate  glass  at  least  one-fourth 
inch  in  thickness  is  used. 

Every  cabinet  should  be  marked  with  manufac- 
turer's name,  where  the  name  can  be  plainly  seen 
when  the  cabinet  is  installed. 

Arc  Lamps  should  be  carefully  isolated  from  in- 
flammable material,  should  be  provided  at  all  times 
with  a  glass  globe  surrounding  the  arc  and  se- 
curely fastened  upon  a  closed  base.  No  broken  or 
cracked  globes  should  be  used,  as  they  are  designed 
to  prevent  hot  bits  of'  carbon  or  even  an  entire 
carbon  from  falling  to  the  floor  should  it  fall  from 
the  carbon  holder.  All  globes  for  inside  work 
should  be  covered  with  a  wire  netting 'having  a 
mesh  not  exceeding  one  and  one-quarter  inches,  to 
retain  the  pieces  of  the  globe  in  position  should  the 
latter  become  broken  from  any  cause.  A  globe 
thus  broken  should  be  replaced  at  once.  When  arc 
lamps  are  used  in  rooms  containing  readily  in- 
flammable material  they  should  be  provided  with 
approved  spark  arresters,  which  should  be  made 
to  fit  so  closely  to  the  upper  orifice  of  the  globe 
that  it  will  be  impossible  for  any  sparks  thrown 
off  by  the  carbons  to  escape.  It  is  safe  to  use  plain 
carbon  and  not  copper-plated  ones  in  such  rooms, 
or  better  still,  an  enclosed  arc  lamp,  one  having 
its  carbons  enclosed  in  a  practically  tight  glass 
globe  which  is  inside  the  outer  globe.  Where 
hanger-boards  are  not  used  arc  lamps  should  be 

130 


hung  from  insulating  supports  other  than  their  con- 
ductors. 

All  arc  lamps  should  be  provided  with  reliable 
tops  to  prevent  carbons  from  falling  out  in  case 
the  lamps  become  loose,  and  all  exposed  parts  should 
be  carefully  insulated  from  the  circuit.  Each  lamp 
for  constant  current  systems,  should  be  provided 
with  an  approved  hand  switch,  and  also  an  auto-, 
matic  switch  that  will  shunt  the  current  around  the 
carbons,  so  that  the  lamp  will  thus  cut  itself  out 
of  circuit  should  the  carbons  fail  to  feed  properly. 
If  the  hand  switch  is  placed  anywhere  except  on 
the  lamp  itself  it  should  comply  in  every  respect 
with  the  requirements  for  switches  on  hanger- 
boards  as  described  under  the  latter  heading. 

Arc  Light  Wiring  (High  Potential).  All  wir- 
ing for  high  potential  arc  lighting  circuits  should 
be  done  with  "Rubber  Covered"  wire.  The  wires 
should  be  arranged  to  enter  and  leave  the  building 
through  an  approved  doubled  contact  service  switch 
which  should  close  the  main  circuit  and  disconnect 
the  wires  in  the  building  when  turned  "off"  and  be 
so  constructed  that  they  will  be  automatic  in  their 
action,  not  stopping  between  points  when  started 
and  to  prevent  arcing  between  points  under  any 
circumstances,  and  should  indicate  plainly  whether 
the  current  is  "on"  or  "off."  Never  use  snap 
switches  for  arc  lighting  circuits.  All  arc  light 
wiring  of  this  class  should  be  in  plain  sight  and 
never  enclosed,  except  when  required,  and  should 
be  supported  on  porcelain  or  glass  insulators  which 
separate  the  wires  at  least  one  inch  from  the  sur- 

131 


face  wired  over.  The  wires  should  be  kept  rigidly 
at  least  eight  inches  apart,  except  of  course  within 
the  lamp,  hanger-board  or  cut-out  box  or  switch. 
On  side  walls  the  wiring  should  be  protected  from 
mechanical  injury  by  a  substantial  boxing,  retain- 
ing an  air  space  of  one  inch  around  the  conductors, 
closed  at  the  top  (the  wires  passing  through  bushed 
holes),  and  extending  not  less  than  seven  feet  from 
the  floor.  When  crossing  floor  timbers  in  cellars 
or  in  rooms,  where  they  might  be  exposed  to  injury, 
wires  should  be  attached  by  their  insulating  sup- 
ports to  the  under  side  of  a  wooden  strip  not  less 
than  one-half  an  inch  in  thickness. 

Arc  Lamp  on  Low  Potential  Circuits  should 
have  a  cut-out  for  each  lamp  or  series  of  lamps. 
The  branch  conductors  for  such  lamps  should  have 
a  carrying  capacity  about  50  per  cent,  in  excess 
of  the  normal  current  required  by  the  lamp  or 
lamps  to  provide  for  the  extra  current  required 
when  the  lamps  are  started  or  should  a  carbon  be- 
come stuck  without  over-fusing  the  wires.  If  any 
resistance  coils  are  necessary  for  adjustment  or 
regulation,  they  should  be  enclosed  in  non-combus- 
tible material  and  be  treated  as.  sources  of  heat ; 
it  is  preferable  that  such  resistance  coils  be  placed 
within  the  metal  framework  of  the  lamp  itself. 
Incandescent  lamps  should  never  be  used  for  re- 
sistance devices.  These  lamps  should  be  provided 
with  globes  and  spark  arresters,  as  in  the  case  of 
arc  lamps  on  high-potential  series  circuits,  except 
when  the  enclosed  arc  lamps  are  used. 

Economy  Coils  or  compensator  coils  for  arc 
lamps  should  be  mounted  on  glass  or  porcelain,  al- 

132 


lowing  an  air  space  of  at  least  one  inch  between 
frame  and  support,  and  in  general  to  be  treated 
like  sources  of  heat. 

Hanger  Boards  should  be  so  constructed  that 
all  wires  and  current-carrying  devices  thereon  will 
be  exposed  to  view  and  thoroughly  insulated  on  non- 
combustible,  non-absorptive  insulating  substance, 
such  as  porcelain. 

All  switches  attached  to  the  hanger-board  should 
be  so  constructed  that  they  will  be  automatic  in 
their  action,  cutting  off  both  poles  to  the  lamp,  not 
stopping  between  points  under  all  circumstances. 

Electric  Heaters  should  always  be  treated  as 
sources  of  heat  and  kept  away  from  inflammable 
materials.  Each  heater  should  have  a  cut-out  and 
indicating  switch  and  all  attachments  from  the  feed 
wires  to  the  heater  should  be  kept  in  plain  sight, 
easily  accessible  arid  protected  from  interference. 
Each  heater  should  have  a  name  plate  giving  the 
maker's  name,  and  the  normal  capacity  in  volts  and 
amperes. 

Car  House  Wiring.  All  trolley  wires  in  car 
houses  should  be  securely  supported  on  insulating 
hangers.  The  trolley  hangers  should  be  placed  close 
enough  together  to  prevent  the  trolley  wire,  should 
it  break  from  any  cause,  from  coming  in  contact 
with  the  floor  or  rails  within  the  building,  or  even 
in  contact  with  the  ironwork  on  the  trucks  or 
wheels  of  the  car,  as  it  hangs  down.  A  broken 
trolley  wire  in  this  way  would  produce  dangerous 
arcing  and  probably  start  a  fire. 

All  the  wires  in  the  car  house  should  be  con- 

133 


trolled  by  a  cut-out  switch,  located  on  a  pole  at 
least  100  feet  from  the  building,  so  that  in  case 
of  fire  or  for  other  reasons  all  wires  could  be  con- 
trolled from  that  point.  The  current  should  al- 
ways be  cut  out  of  the  car  house  when  the  same 
is  not  in  use  or  the  road  not  in  operation.  All 
lamps  and  stationary  motors  used  in  car  houses 
should  be  installed  in  such  a  way  that  one  main 
switch  can  control  the  whole  of  each  installation 
independently  of  the  main  feeder  switch.  No  port- 
able incandescent  lamps  or  twin  wire  should  be 
used,  except  in  the  car  pits,  where  they  may  be  used 
when  connections  are  made  by  two  approved  rub- 
ber-covered flexible  wires,  .  properly  protected 
against  mechanical  injury,  and  all  such  pit  wiring 
be  controlled  by  a  separate  switch  for  each  pit 
placed  outside  of  the  pit.  All  wiring  for  lights  or 
motors  within  the  car  house  should  be  with  ap- 
proved rubber-covered  wire  and  supported  on  sin- 
gle porcelain  or  glass  insulators  which  separate  the 
wires  from  surface  wired  over  by  one  inch.  No 
system  of  feeder  distribution  should  center  in  the 
car  house. 

All  rails  within  the  building  should  be  bonded  at 
each  joint  with  annealed  copper  wire,  not  smaller 
than  No.  oo  B.  &  S.  gage. 

When  cars  are  run  in  the  house  they  should  not 
be  left  with  their  trolleys  in  contact  with  the  trol- 
ley wire,  as  frequent  fires  have  been  caused  by  the 
motorman  or  conductor  forgetting  to  turn  off  the 
car  heater  current  or  other  car  wiring,  and  during 
the  course  of  the  night,  or  other  times,  "burn-outs" 

1S4 


have  occurred,  followed  by  fire,  and,  as  once  hap- 
pened in  the  course  of  the  writer's  experience,  the 
total  loss  of  a  large  car  house  and  a  number  of 
valuable  cars  and  other  stock.  Current  from  trol- 
ley systems,  having  a  grounded  return  wire,  should 
never  be  used  for  any  purpose  in  or  on  buildings 
other  than  car  houses  or  their  power  stations. 

Approved  Apparatus  and  Supplies.  Every  ar- 
ticle or  fitting  intended  for  use  in  electrical  wiring 
or  construction  or  in  connection  therewith  should, 
before  being  manufactured  or  placed  upon  the  mar- 
ket, be  submitted  to  the  Underwriters'  Laboratories, 
207  East  Ohio  street,  Chicago,  for  examination  and 
report.  Branch  offices  are  located  in  thirty-two 
other  cities  of  the  United  States  and  Canada.  The 
New  York  office,  at  135  William  street,  is  equipped 
for  the  conduct  of  examinations  and  tests  of  all 
electrical  devices  under  the  same  conditions  as  those 
afforded  at  the  principal  office  and  testing  station 
in  Chicago. 

The  amounts  of  the  fees  are  in  proportion  to  the 
nature  and  extent  of  the  work  required  in  exam- 
inations and  tests.  When  such  article  or  device  is 
approved  and  found  safe  and  suitable  for  the  use 
intended,  it  is  placed  on  the  List  of  Electrical  Fit- 
tings issued  semi-annually  by  the  National-  Board 
of  Fire  Underwriters,  for  use  in  accordance  with 
the  rules  and  requirements  of  the  National  Elec- 
trical Code  as  given  in  the  foregoing  pages  of  this 
book. 

When  buying  electrical  supplies  of  any  descrip- 
tion make  sure  that  they  have  been  approved,  or 
that  their  use  will  be  permitted.  If  there  is  any 

135 


question  about  it,  make  your  supply  dealer,  or  the 
manufacturer  give  you  a  guarantee  that  they  will 
be  approved  by  the  Fire  Underwriters'  Inspector  if 
installed  in  accordance  with  the  rules  and  require- 
ments of  the  National  Electrical  Code. 

Electrical  Inspection.  The  principal  points  re- 
garding the  safe  installation  of  dynamos,  motors,  ^ 
outside  and  inside  wiring,  as  required  by  the  insur- 
ance underwriters,  have  been  briefly  set  forth  in 
this  little  book,  which  has  been  compiled  simply 
for  reference  and  not  as  a  teacher — a  book  designed 
to  settle  most  of  the  doubtful  questions  which  might 
arise  on  the  mind  of  the  engineer  or  contractor  as 
to  just  what  will  be  considered  safe  by  insurance 
inspectors.  There  will  probably  arise  questions 
which  cannot  be  settled  by  reference  to  the  sugges- 
tions herein  contained,  and,  therefore-,  a  great  deal 
has  to  be  left  to  the  judgment  of  the  constructing 
engineer  and  inspector.  In  every  such  case  the 
Inspection  Department  having  jurisdiction  should 
be  consulted  with  perfect  assurance  that  nothing 
unreasonable  will  ever  be  demanded  in  the  way  of 
special  construction. 

Every  piece  of  wiring  or  electrical  construction 
work,  whether  open  or  concealed,  should  be  in- 
spected, and  notice,  therefore,  should  always  be 
sent  by  the  contractor  or  engineer  to  the  board  hav- 
ing jurisdiction  immediately  upon  completion  of 
any  work.  Negligence  in  this  matter  has  frequent- 
ly caused 'floors  to  be  torn  up  when  doubtful  work- 
has  been  suspected,  and  at  the  cost  of  the  parties 
who  installed  the  wiring. 

136 


WIRE    TABLE,     STANDARD     ANNEALED'    COPPER. 


Case 
No. 
B.  &  S. 

Diameter 
in  Mils 

at  20°  C 

Cross 
Section 
Circular 
Mils 

Ohms  per  1000  Feet  * 

0°  C 
(=32"  F) 

20°  C 
(=68°  F) 

50°  C 
(=122°  F) 

0000 
000 
00 

460.0 
409.6 
364.8 

211   600. 
167  800. 
133   100. 

0.045   Ib 
.0.36  <J5 
.071  81 

0.049  01 
.061   80 
.077  93 

0.054   79 
.069   09 
.087   12 

0 
1 
2 

324.9 
289.3 
257.6 

105   500. 
83  690. 
66  370. 

.09055 
.1142 
.1440 

.09827 
.1239 
.1563 

.1099 
.1385 
.1747 

3 
•  4 
5 

229.4 
204.3 
181.9 

32   640. 
41   740. 
33   100. 

.1816 

.2289 
.288  1 

.1970 
.2485 
.3133 

.2203 
.2778 
.8502 

6 
8 

162.0 
144.3 
128.5 

26   250. 
20  820. 
16   510. 

.3640 
.4590 

.5788 

.3951 
.4982 
.6282 

.4416 
.5569 
.7023 

9 
10 
11 

114.4 

101.9 
90.74 

13   090. 
10  380. 
8234. 

.7299 
.9203 
1.161 

.7921 
.998y 
1.260 

.8855 
1.117 
1.408 

12 

13 
14 

80.81 
71.96 
64.08 

6530. 
5178. 
4107. 

1.463 
1.845 
2.32T 

1.588 
2.003 
2.525 

1.775 
2.239 
2.823 

15 
16 
17 

57.07 
50.82 
45.26 

3257. 
2583. 
2048. 

2.934 

3.700 
4.666 

3.184 

4.016 
5.064 

3  .  560 
4.489 
5.660 

18 
19 
20 

40.30 
35.89 
31.96 

1624. 

1288. 
1022. 

5.883 
7.418 
9.355 

6  .  385 
8.051 
10.15 

7.138 
9.001 
11.35 

21 
22 
23 

28.46 
25.35 
22.57 

810.1 
642.4 
509  .  5 

11.80 
14.87 
18.76 

12  .  80 
16.14 
20.36 

14.31 
18.05 
22.76 

24 
25 

26 

20.10 
17.90 
15.94 

404.0 
320.4 
.      254.1 

23.65 
29.82 
37.61 

25.67 
32.37 
40.81 

28.70 
36.18 
45.63 

27 
28 
29 

14.20 
12.64 
11  .  26 

201.5 
159.8 
126.7 

47.42 
59.80 
75.40 

51.47 
64.90 
81.83 

57.53 
72.55 
91.48 

30 
31 
32 

10.03 

8.928 
7.950 

100.5 
79.70 
63.21 

95.08 
19.9 
51.2 

103.2 
130*1 
164.1 

115.4 
145.5 
183.4 

33 
34 
35 

7  .  080 

r>.3<r> 

5.615 

50  .  13 
39.57 
31.52 

90.6 
40.4 
03.1 

206.9 
260.9 
329.0 

231.3 
291.7 
367.8 

*  Resistance  af  the  stated  temperatures  of  a  wire  whose  length 
is    1000    feet    at    20°    C.    (Bureau    of    Standards) 
137 


WIRE  TABLE,   STANDARD   ANNEALED  COPPER.— 
.  CONTINUED. 


Gage 
No. 

B.  &S. 

Diameter 
in  Mils 
at  20°  C 

Pounds 
per 
1000  Feet 

Feet  per  Ohm  * 

0°  C 
(=32°  F) 

20°  C 

(=68°  F) 

20  400. 
16   180 
12  830. 

50°  C 
(=122°  F) 

18  250. 
14  470. 
11  480. 

000 
000 
00 

460.0 
409.6 
3t>4.8 

340.5 
507.9 
402.8 

22  140. 
17  5fiO. 
13  930. 

0 

1 

2 

324.9' 
J2S9.3 
257.6 

319.5 
253.3 
200.9 

11  040. 

8758. 
6946. 

10  180 

8070. 
6400. 

9103. 
7219. 
5725. 

3 
4 
5 

229.4 
204.3 
181.9 

159.3 

126.4 
100.2 

5508. 
4368. 
3464. 

5075. 
4025. 
3192. 

4540. 
3600, 
2855. 

6 

7 
8 

162.0 
144.3 

128.5 

79.46 
63.02 
49.98 

2747. 
2179. 
1728. 

2531. 
2007. 
1592. 

2264. 
1796. 
1424. 

9 

10 
11 

114.4 
101.9 
90.74 

39.63 
31.43 
24.92 

1370. 

1087. 
861.7 

1262. 
1001. 
794.0 

1129. 

895.6 
710.2 

12 
13 
14 

80.81 
71.96 
64.08 

19.77 
15.68 
12.43 

683.3 
541.9 
429.8 

629.6 
499.3 
396.0 

563.2 
446.7 
354.2 

15 
16 
17 

57.07 
50.82 
45.26 

9.858 
7.818 
6.200 

340.8 
270.3 
214.3 

314.0 
249.0 
197.5 

280.9 
2.2.8 
176.7 

18 
19 
20 

40.30 
35.89 
31.96 

4.917 
3.899 
3.092 

170.0 
134.8 
106.9 

156.6 
124.2 
98.50 

140.1 
111.1 
88.11 

21 
22 
23 

28.46 
25.35 
22.57 

2.452 
1.945 
1.542 

84.78 
67.23 
53.32 

78.11 
61.95 
49.13 

69.87 
55.41 
43.94 

24 
25 

26 

20.  JO 
17.90 
15.94 

1.223 
0.9699 
.7692 

42.28 
-S3.  53 
26.59 

38.96 
30.90 
24.50 

34.85 

27.64 
21.92 

27 
28 
29 

14.20 
12.64 
11.26 

.6100 
.4837 
.3836 

21.09 
16.72 
13.26 

19.43 
15.41 
12.22 

17.38 
13.78 
10.93 

30 
31 
32 

10.03 
8.928 
7.950 

.3042 
.2413 
.1913 

10.52 
8.341 
6.614 

9.691 

7.68") 
6.095 

8.669 
6.875 
5.452 

33 
34 
35 

7.0RO 
6  .  305 
5.615 

.1517 
.1203 
.095  42 

5.245 
4.160 
3.299 

4.833 
3  .  83^ 
3.040 

4.323 
3.429 
2.719 

*  Length  at  20°  C  of  a  wire  whose  resistance  is  1  ohm   at   the 
stated  temperatures.      (Bureau    of    Standards). 
138 


WIRE   TABLE,    STANDARD   ANNEALED   COPPER. 
—CONTINUED. 


Gage 
No. 
B.  &S. 

Diameter 
in  Mils 
at  20°  C 

Ohms  per  Pound 

0°  C 
(=32°  F) 

20°  C 
(=68°  F) 

50°  C 
(=122°  F) 

0000 
000 
00 

460.0 
409.6 
364.8 

0.000  070   51 
.000  1121 
.000  1783 

0.000  076  52 
.000  1217 
.000  1935 

0.000  085  54 
.000  1360 
.000  2163 

0 
1 

2 

324.9 
289.3 
257.6 

.000  2835 
.000  4507 
.000  7166 

.000  3076 
.000  4891 
.000  7778 

.000  3439 
.000  5468 
.000  8695 

3 
4 
5 

229.4 
204.3 
181.9 

.001   140 
.001   812 
.002  881 

.001   237 
.001   966 
.003  127 

.001  383 
.002   198 
.003  495 

6 
7 
8 

162.0 
144.3 
128.5 

.004  581 
.007  284 
.011   58 

.004  972 
.007  905 
.012  57 

.005  558 
.008  838 
.014  05 

9 

10 
11 

114.4 
101.9 
90.74 

.018  42 
•      .029  28 
.046  56 

.019  99 
.031   78 
.050  53 

.022  34 
.035  53 
.056  49 

12 
13 
14 

80.81 
71.96 
64.08 

.074  04 
.1177 
.1872 

.080  35 
.1278 
.2032 

.089  83 
.1428 
.2271 

15 

16 
17 

57.07 
50.82 
45.26 

.2976 
.4733 
.7525 

.3230 
.5136 
.8167 

.3611 

.5742 
.9130 

18 
19 
.    20 

40.30 
35  .  89 
31.96 

1.197 
1.903 
3.025 

1.299 
2.065 
3.283 

1.452 

2.308 
3.670 

21 
22 
28 

28.46 
25.35 
22.57 

4.810 
7.649 
12.16 

5.221 
8.301 
13.20 

5.836 
•9.280 
14.76 

24 
25 
26 

20.10 
17.90 
15.94 

19.34 
30.75 

48.89 

20.99 
33.37 
53.06 

23.46 
37.31 
59.32 

27 

28 
29 

14.20 
12.64 
11.26 

77.74 
123.6 
196.6 

84.37 
134.2 
213.3 

94.32 
150.0 
238.5 

CO 
31 
32 

10.03 
8.928 
7.950 

312.5 

407.0 
790.3 

339.2 
539.3 
857.6 

379.2 
602.9 
958.7 

33 

34 

35 

7.080 
6.305 
5.615 

1256. 

1998. 
3177. 

1364. 
216S. 
3448. 

1524. 
2424. 
3854. 

(Bureau  of  Standards) 
139 


WIRE  TABLE,   STANDARD  ANNEALED  COPPER— CONTINUED 


Gasre 
No. 
B.  &S. 

Diameter 
in  Mils 
at  20°  C 

Pounds   per   Ohm 

0°  C 
(=32°  F) 

20°  C 

(=68°  F) 

50°  C 
(=122°  F) 

0000 
000 
00 

460.0 
409.6 
364.8 

14  180. 
8920. 
5610. 

13  070. 
8219. 
5169. 

11   690. 
7352. 
4624. 

(; 

1 

2 

324.9 
289.3 
257.6 

3528. 
2219. 
1395. 

3251. 

2044. 
1286. 

2908. 
1829. 
1150. 

3 
4 
5 

229.4 
?04.3 
181.  9 

877.6 
551.9 
347.1 

.808.6 
508.5 
319.8 

723.3 

454.9 
286.1 

6 

7 
S 

182.0 
It4.3 
128.5 

218.3 
137.3 
86.34 

201  .1 
126.5 
79  .  55 

179.9 
113.2 
71.16 

9 

JO 
11 

114.4 
101.9 
90.74 

54.30 
34.15 
21.48 

50.03 
31.47  . 
19.79 

44.75 
28  .  1  5 

17.70 

12 
13 
14 

80.81 
71.96 
64.08 

13.51 

8.495 
5.342 

12.45 

7.827 
4.922 

11.13 

7.001 
4.403 

15 

16 
17 

57  .  07 
50.82 
45.26 

3.360 
2.113 
1.329 

3.096 
1.947 
1.224 

2.769 
1.742 
1.095 

18 

19 

20 

40.30 
35.89 
31.96 

0.8357 
.5256 
.3306 

0.7700 
.4843 
.3046 

0.6888 
.4332 
.2725 

21 
22 
23 

28.46      •      »     .2079 
25.35                   .1307 
22.57      j             .08222 

.1915 
.1205 
.075   76 

.1713 

.1078 
.067  77 

24 
25 
26 

20.10                  .05171 
17.90                  .03252 
15.94     ;              .02045 

.047  65 
.029  97 
.018  85 

.042  62 
.026   80 
.016   86 

27 
28 
29 

14.20     '             .01286 
12.64                   .008090 
11.26                   .005088      , 

Oil   85 
.007  454 
.004  688 

.010  60 
.006   6C8 
.004   193 

30 
31 
32 

10.03 
8.928 
7.950 

.003200 
.002  012 
.001  266 

.002  948 
.001  854 
.001   166 

.002   637 
.001  659 
.001   043 

33 
34 
35 

7.080 
6.305 
5.615 

.000  7959 
.000  5005 
.000  3148 

.000  7333 
.000  4612 
.000  290"1 

.000  6560 
'  .000   4126 
.000  2595 

(Bureau  of  Standards) 


140 


HOUSE  WIRING. 

Special  Suggestions  and  Recommendations  to  the 
House  Owner,  Architect,  Contractor  and 
Wweman,  with  the  co-operation  of  the  Na- 
tional Electric  Light  Association  Committee  on 
Wiring  Existing  Buildings  and  the  Society  for 
Electrical  Development,  in  Accordance  with  the 
Rules  and  Requirements  of  the  National  Board 
of  Fire  Underwriters. 

Obtaining  Service. 

In  every  case  where  the  electric  wires  have  not 
been  introduced  into  a  house,  it  is  necessary  to  con- 
sult the  central  station  as  to  the  terms  on  which 
service  can  be  obtained. 

When  the  wires  are  not  even  on  the  street  it  will 
always  be  necessary  for  the  central  station  to  make 
an  extension,  involving  additional  mains,  as  the 
electric  wires  in  the  street  are  called,  and  usually 
additional  poles  for  overhead  wires,  or  digging  for 
conduits  for  underground  wires. 

It  may  be  noted  here  that  the  current  for  trolley 
service  is  not  suitable  for  house  lighting,  nor  is 
such  service  allowed  by  the  insurance  interests  in 
any  part  of  the  country. 

No  one  but  the  central  station  representative  can 
determine  the  cost  of  making  an  extension,  and  all 
that  can  be  said  in  this  general  treatise  is  that  some- 
times the  central  station  will  extend  its  wires  with- 
out any  guarantee,  on  the  chance  that  the  new  busi- 
ness will  be  profitable.  In  other  cases  the  prospec- 
tive customer  is  asked  to  guarantee  a  definite  in- 
come for  a  term  of  years,  or  to  make  a  deposit 
towards  the  cost  of  the  extension,  to  be  returned 

141 


out  of  the  income ;  or  in  extreme  cases,  even  to  pay 
the  whole  cost.  Each  case  has  to  be  considered 
separately;  but  in  this  country  a  somewhat  general 
rule  is  to  make  extensions  when  the  annual  income, 
either  estimated  or  guaranteed,  is  equal  to  about 
half  the  cost  of  the  additional  investment,  or  cost 
of  the  extension  beyond  the  point  to  which  the 
lines  have  been  already  built. 

In  regard  to  whether  the  service  is  overhead  or 
underground,  this  usually  depends  on  the  character 
of  the  neighborhood,  dense  city  districts  being  sup- 
plied underground,  and  suburban  or  country  dis- 
tricts overhead. 

If  in  a  district  where  the  wires  are  underground, 
the  central  station  extends  the  mains  along  the 
street,  and  usually  branches  from  the  mains  to  the 
lot  line  without  further  charge  for  the  branch. 
Sometimes  the  street  construction  is  such  that  the 
house  service  comes  from  the  wire  directly  oppo- 
site. In  other  cases  there  are  manholes  in  the  street 
at  convenient  intervals,  and  the  wires  run  directly 
from  such  manhole  to  the  house. 

Sometimes  a  charge  is  made  by  the  central  sta- 
tion for  the  whole  of  the  branch  to  the  house,  but 
more  usually  there  is  no  charge  for  the  work  in 
the  public  streets,  and  often  the  wire  is  carried  free 
to  the  house  wall,  especially  if  the  house  is  close  to 
the  street.  If,  however,  there  is  a  wide  lawn  a 
charge  is  often  made,  running  from  75  cents  to 
$1.50  per  foot,  according  to  circumstances.  In  the 
case  of  new  houses  it  is  often  convenient  to  use  the 
same  trench  or  conduits  for  the  telephone  wires 
also,  and  sometimes  even  for  the  water  pipe. 

141 


As  the  central  station  will  always  either  do  this 
underground  work  itself  or  furnish  definite  and 
complete  specifications,  no  further  reference  need 
be  made  to  it  here. 

In  the  case  of  overhead  wires  questions  about 
the  extension  of  the  central  station  wires  in  the 
street  come  up.  The  householder  should  appreciate 
that  overhead  wires  are  installed  only  in  districts 
where  the  cost  of  underground  is  prohibitive,  so 
that  if  the  central  station  cannot  obtain  the  right  to 
set  the  necessary  poles  in  such  districts  it  may  not 
be  able  to  extend  the  wires  at  all. 

When  the  necessary  poles  are  near  enough  the 
central  station  will  usually  run  the  wires  from  the 
pole  to  the  house  without  further  charge. 

In  other  cases,  as  when  the  house  sets  far  back, 
or  when  for  some  special  reason  the  wires  have 
to  enter  the  house  in  the  rear,  it  may  be  necessary 
to  set  poles  on  the  private  property,  for  which  work 
the  central  station  will  frequently  make  a  charge, 
which  should  run  from  say  $10  to  $50,  about  $25 
for  each  pole  together  with  the  wire,  cross  arms, 
insulators,  etc. 

Of  course,  when  the  customer  is  willing  to  pay 
for  it,  the  central  station  will  run  its  wires  down 
the  pole  into  the  ground  and  supply  the  house  by 
an  underground  service,  even  in  overhead  districts. 

The  Code  rules  governing  outside  work  for  both 
overhead  and  underground  are  as  follows : ; 

a.  Line  wires  must  have  an  approved  weather- 
proof or  rubber  insulating  covering  (see  p.  67). 
That  portion  of  the  service  wires  between  the  main 
cut-out  and  switch  and  the  first  support  from  the 

143 


cut-out  or  switch  on  outside  of  the  building  must 
have  an  approved  rubber  insulating  covering,  but 
from  the  above-mentioned  support  to  the  line,  ex- 
cept when  run  in  conduit,  may  have  an  approved 
weatherproof  insulating  covering  if  kept  free  from 
awnings,  swinging  signs,  shutters,  etc. 

b.  Must  be  so  placed  that  moisture  cannot  form 
a  cross  connection  between  them,  and  except  when 
run  in  conduit,  not  less  than  a  foot  apart]  and  not 
in  contact  with  any  substance  other  than  their  in- 
sulating supports.     Wooden  blocks  to  which  insu- 
lators are  attached  must  be  covered  over  their  entire 
surface  zuith  at  least  two  coats  of  waterproof  paint. 

For  conduit  work,  zvires  must  be  placed  so  as  to 
conform  to  rules  for  unlined  conduit  except  that 
conduit  system  must  be  waterproof  (see  p.  96). 

c.  Must  be  at  least  seven  feet  above  the  highest 
point  of  flat  roofs  (see  p.  43)  and  at  least  one  foot 
above  the  ridge  of  pitched  roofs  over  which  they 
pass  or  to  which  they  are  attached  and  roof  struc- 
tures must  be  substantially  constructed. 

d.  Must,  zvhere  exposed  to  the  weather,  be  pro- 
vided with  petticoat  insulators  of  glass  or  porce- 
lain (see  pp.  40  Mid  41);  porcelain  knobs  or  cleats 
and  rubber  hooks  will  not  be  approved.     Wires  on 
the  exterior  walls  of  buildings  must  be  supported 
at  least  every  fifteen  feet,  the  distance  between  sup- 
ports to  be  shortened  if  wires  are  liable  to  be  dis- 
turbed. 

Where  not  exposed  to  the  weather,  low  poten- 
tial wires  may  be  supported  on  glass  or  porcelain 
knobs  which  zvttl  separate  the  wires  at  least  one 
inch  from  the  surface  ivired  over,  supports  to  be 

144 


placed  at  least  every  four  and  one-half  feet. 

e.  Must  be  so  spliced  or  joined  as  to  be  both 
mechanically   and   electrically   secure   without  *  sol- 
der (see  p.  40).     The  joints  must  then  be  soldered, 
to  insure  preservation,  and  covered  ixnth  an  insula- 
tion equal  to  that  on  the  conductors. 

All  joints  must  be  soldered,  unless  made  with 
some  form  of  approved  splicing  device  (see  p.  40). 

f.  Must,  ivJiere  they  enter  buildings,   have  drip 
loops  outside,  and  the  holes  through  which  the  con- 
ductors pass  must  be  bushed  with  non^combustible, 
non-absorptive,  insulating   tubes    slanting    upward 
toward  the  inside. 

For  low-potential  systems  the  service  wires  may 
be  brought  into  buildings  through  a  single  iron  con- 
duit. The  conduit  to  be  equipped  with  an  approved 
service-head  (see  pp.  42  and  44).  The  inner  end 
must  extend  to  the  service  cut-out,  and  if  a  cabinet 
is  required  by  the  Code  must  properly  enter  the 
cabinet. 

g.  Electric  light  and  power  wires  must  not  be 
placed  on  the  same  cross-arm  with  telegraph,  tele- 
phone or  similar  wires,  and  when  placed  on  the 
same  pole  with  such  zvires  the  distance  between  the 
two  inside  pins  of  each  cross-arm  must  not  be  less 
than  twenty-six  inches. 

h.  The  metallic  sheaths  of  cables  must  be  per- 
manently and  effectively  connected  to  "earth'  (see 
pp.  46-50). 

Although  not  specified  in  the  Code,  bare  wires 
are  sometimes  used,  especially  through  uninhabited 
and  isolated  territories,  free  from  other  wires  (see 
tables,  pp.  62,  63,  210,  211). 

145 


Bare  wire  is  also  used  for  high  tension  wires, 
the  theory  being  that  only  the  insulators  and  not 
the  'covering  are  relied  on  for  pole  insulation. 
Hence,  where  there  is  no  danger  of  other  wires  or 
trees  coming  near  them,  bare  wire  is  satisfactory. 
If  there  are  other  wires  or  trees  near,  and  the  ten- 
sion is  below  say  5000,  then  weatherproof  insula- 
tion saves  enough  trouble  from  crosses  with  other 
wires,  branches,  etc.,  to  be  worth  the  cost.  When, 
however,  the  voltage  is  above  5000,  the  protection 
of  the  covering  is  so  slight  as  not  to  be  worth  while. 

It  should  be  noted  that  wires  should  be  kept  well 
clear  of  trees,  as  branches  may  blow  onto  the  wires 
and  cause  trouble,  even  if  clear  of  the  wires  in  calm 
weather. 

Also,  many  companies  consider  it  undesirable  to 
attach  wires  to  trees,  but  prefer  to  set  independent 
poles,  even  at  an  added  expense,  on  the  ground  that 
in  the  long  run  the  cost  is  less.  Where  tree  wiring 
may  be  necessary,  suggestions  are  illustrated  on 
page  41. 

Guard  arms  should  be  placed  on  all  corner  poles 
(see  pages  40  and  64). 

This,  however,  applies  more  often  to  poles  on 
street  corners  rather  than  from  pole  to  house. 

In  alternating  current  systems  the  wires  in  the 
street  are  usually  of  high  voltage  (2000  to  4000 
volts)  and  a  transformer  is  used  for  transforming 
the  voltage  to  no  or  220  volts. 

The  rule  governing  transformer  installation  is 
given  on  page  147. 

Current  Supply. 

Art.  i :  In  designing  a  house  wiring  installation, 

146 


it  is  necessary  to  know  whether  the  current  is  direct 
or  alternating  and  the  voltage  of  the  supply  serv- 
ice. If  alternating  it  is  also  necessary  to  know  the 
phase  and  cycle. 

In  some  large  cities  direct  current  is  used  and 
also  in  places  where  owners  have  private  generat- 
ing plants.  In  most  of  the  intermediate  and  smaller 
cities,  however,  and  in  practically  all  suburban  dis- 
tricts, the  supply  is  from  alternating  current. 

In  practically  all  residences,  except  very  large 
ones  with  large  individual  motors,  the  alternating 
current  is  delivered  in  what  is  known  as  single 
phase,  requiring  but  one  transformer,  and  this  con- 
dition is  assumed  throughout  this  section  of  the 
book. 

The  transformer  for  supplying  a  residence  is 
generally  located  on  a  pole  (see  p.  49),  or  in  an 
underground  vault,  near,  or  inside,  the  building  and 
the  transformer  is  designed  with  two  or  three 
wires,  according  to  the  system  used,  coming  from  it 
on  the  house  or  service  side. 

The  Code  rule  is  as  follows : 

Transformers  must  not  be  placed  inside  of  build- 
ings without  special  permission. 

Must  be  located  as  near  as  possible  to  the  point 
at  which  the  primary  wires  enter  the  building. 

Must  be  placed  in  an  enclosure  constructed  of 
fire-resisting  material;  the  enclosure  to  be  used  only 
for  this  purpose,  and  to  be  kept  securely  locked, 
and  access  to  the  same  allowed  only  to  responsible 
parties. 

The  transformer  case  must  be  permanently  and 
effectually  grounded,  and  the  enclosure  in  which 

147 


the  transformers  are  placed  must  be  practically  air- 
tight, except  that  it  must  be  thoroughly  ventilated 
to  the  outdoor  air,  if  possible  through  a  chimney  or 
Hue.  There  should  be  at  least  six  inches  air  space 
on  all  sides  of  the  transformer. 

In  equipments  with  not  more  than  fifty  lights 
and  outlets  many  lighting  companies  deliver  the 
current,  from  the  transformer  to  the  building,  on  a 
two-wire  system  at  about  1 10  volts  and  without  the 
use  of  the  third  or  neutral  wire. 
Voltage. 

Art.  2 :  With  the  three-wire  system  the  voltage 
between  the  two  outside  wires  is  generally  about 
220  volts  and  the  voltage  between  the  neutral  (mid- 
dle) wire  and  either  outside  wire  is  about  no  volts. 
The  no-volt  outlets,  for  lights  and  small  appliances 
are  placed  on  two-wire  branch  circuits,  balanced  on 
each  side  of  this  neutral  wire.  Larger  appliances 
are  often  wound  for  220  volts  and  connected  across 
the  outside  or  22O-volt  circuit. 

For  these  larger  power  appliances  and  motors 
22O-volt  apparatus  is  used  for  the  purpose  of  re- 
ducing the  size  of  the  wires  supplying  them.  Small 
heating  appliances  where  considerable  heat  must  be 
generated  are  almost  universally  made  for  no 
volts. 

Bell  and  telephone  systems  require  but  low  volt- 
age (4-6  volts)  and  small  currents  and  therefore 
are  seldom  dangerous  from  a  fire  standpoint,  when 
kept  away  from  contact  with  light  and  power  wir- 
ing. This  portion  of  the  installation  is  not  inspected 
by  insurance  representatives,  except  to  see  that  the 
wires  do  not  come  in  contact  at  any  point  with 

148 


electric  lighting  or  power  circuits,  from  which  they 
must  be  kept  entirely  separate. 

Service  Feeders. 

Art.  3 :  In  most  of  the  larger  cities  the  feed  wires 
come  directly  into  the  cellar  underground  and  in 
many  cases  where  the  wires  are  overhead  on  poles, 
the  owner  prefers  to  have  the  wires  brought  into 
the  house  underground  from  the  nearest  pole,  al- 
though in  this  case,  the  owner  must  pay  for  the 
underground  portion  of  the  work. 

Where  the  lighting  companies'  pole  on  the  high- 
way is  not  over  sixty  or  seventy  .feet  (60'  or  70') 
from  the  residence,  the  service  company  will  gen- 
erally bring  its  service  wires  overhead  to  the  house 
without  charge  and  in  such  cases  it  is  good  prac- 
tice to  have  the  house  wiring  carried  through  the 
cellar  wall  to  the  outside  of  the  house  and  then 
rise  in  a  rigid  iron  conduit  to  meet  the  overhead 
wiring,  the  end  of  the  conduit  being  turned  over  or 
fitted  with  an  appliance  such  as  a  service  head  or 
pot-head  which  will  prevent  the  entrance  of  water 
(see  p.  44). 

At  this  point,  insulators  are  placed  on  the  side 
of  the  house  to  take  the  strain  of  the  wires  from 
the  pole  to  the  house,  and  then  a  loop  is  made,  con- 
necting to  the  wires  in  the  conduit  arranged  so  that 
the  wires  come  out  of  the  conduit  at  a  downward 
angle  to  prevent  rain  water  from  running  along  the 
wires  into  the  conduit. 

Main  Switch  and  Meters. 

Art.  4:  The  service  switch  (see  pp.  108-112) 
for  cutting  off  the  entire  electrical  supply  of  the 
house  and  the  meters  furnished  and  installed  by 

149 


the  lighting  company  should  be  located  at  some 
accessible  point  as  in  the  cellar  close  to  where  the 
wires  come  through  the  wall.  This  makes  it  un- 
necessary for  the  meter  reader,  who  comes  once  a 
month,  to  go  through  the  main  living  portion  of  the 
residence. 

Where  a  different  rate  is  charged  for  different 
classes  of  service  there  should  be  a  different  meter 
for  each  class.  Many  service  companies  make  dif- 
ferent rates  for  light,  for  power  and  for  heating, 
cooking  and  refrigeration.  Most  companies  will 
furnish  and  connect  3-wire  meters  for  power  and 
cooking,  etc.,  as  well  as  for  light,  so  that  both  110- 
volt  and  22O-volt  apparatus  may  be  used  on  the 
same  meter  by  balancing  on  each  side  of  the  neutral 
wire,  as  explained  in  Art.  2.  The  service  company 
should  be  consulted  as  to  meter  arrangements. 

Current  Costs. 

Art.  5 :  The  costs  given  below  for  operating  vari- 
ous appliances  are  based  on  the  ratio  common  with 
many  companies  throughout  the  United  States,  viz : 

Lighting,  roc.  per  kilowatt-hour. 

Power,  8c.  per  kilowatt-hour. 

Heating,  cooking  and  refrigeration,  5c.  per  kilo- 
watt-hour. 

Rates  varying  from  the  above  will  cause  a  like 
change  in  the  operating  costs.  Electricity  is  sold 
at  so  much  per  kilowatt-hour.  A  kilowatt  means 
1000  watts  (see  pp.  195  and  200). 

A  kilowatt-hour  is  the  equivalent  of  1000  watts 
continually  consumed  for  one  hour  (see  p.  201). 
Watts  (see  pp.  195  and  201)  are  the  product  of  the 
volts  by  the  amperes.  Thus,  40  25-watt  Mazda  or 

150 


Tungsten  lamps  (each  giving  about  21  candle-pow- 
er) all  continuously  in  use  for  one  hour,  or  one 
such  lamp  burning  for  40  hours  would  in  either 
case  consume  one  kilowatt-hour  and  cost  about  ice. 
at  the  above  rate  (see  Lamp  Data,  p.  115). 

For  cooking,  current  at  3c.  per  kilowatt-hour  is 
about  the  equivalent  of  artificial  gas  at  goc. 

Grounding. 

Art.  6:  In  two-wire  system  (see  Art.  i),  one  side 
of  the  service  switch  and  in  the  three-wire  system, 
the  neutral  (middle)  of  the  service  switch  (in  both 
cases  on  the  incoming  side),  should  be  grounded  by 
means  of  a  copper  wire  to  the  water  supply  pipe 
on  the  supply  side  of  the  water  meter. 

By  grounding  is  meant  a  solid,  permanent  con- 
nection to  the  earth  or  ground  by  means  of  cen- 
nection  to  water  pipes,  or  plates  buried  in  the 
ground  (see  pp.  46-50).  The  result  is  that  if  either 
outside  the  house  or  in  it  anyone  touches  this  neu- 
tral or  grounded  wire,  as  at  a  lamp  socket,  and  also 
touches  or  makes  connection  with  the  ground,  as 
through  a  gas  pipe  or  radiator,  there  is  no  difference 
of  potential,  while  if  either  the  positive  or  negative 
wire  is  touched  only,  the  system  potential,  as  120 
or  240  volts,  is  felt,  and  is  considered  perfectly  safe 
while  pressures  above  300  become  dangerous. 

Without  a  ground  connection,  it  is  possible,  in 
ofse  of  an  accident  in  the  street  or  during  a  thunder- 
storm, for  almost  any  pressure  to  get  on  the  wires. 
If  this  happens  they  are  still  safe  so  long  as  no 
connection  is  made  by  a  person  between  the  wires, 
and  no  ground  connection  made  at  all.  If  after 
such  dangerous  pressure  gets  on  the  wires  a  ground 

151 


connection  is  made  somewhere  by  accident,  still 
nothing  happens,  but  then  if  a  person  touch  the 
ungrounded  wire  and  connect  to  ground,  as  through 
a  radiator,  etc.,  he  gets  the  full  pressure. 

On  the  other  hand,  with  a  ground  connection 
made  intentionally,  whenever  any  dangerous  press- 
ure gets  on  the  wires  it  immediately  flows  to  the 
ground,  when  contact  is  made,  through  any  lamp 
socket,  motor,  or  current-using  devices  on  the  sys- 
tem, and  blows  the  fuses  before  any  harm  can  be 
done. 

The  result  is  that  a  ground  connection,  while 
making  it  possible  for  any  person  easily  to  get  the 
normal  voltage,  makes  it  impossible  for  him  to  get 
any  more. 

Where  the  wiring  of  the  house  is  in  conduit,  the 
conduit  system  should  be  continuous  or  electrically 
connected  by  means  of  wires,  and  the  conduit  sys- 
tem also  grounded  in  the  cellar  to  the  water  pipe, 
in  the  same  manner  as  described  above  for  service 
switches.  The  two  ground  wires  should  be  sepa- 
rate, although  they  may  connect  to  the  same  water 
pipe  (see  pp.  92-98). 

House  Mains. 

Art.  7 :  From  the  service  equipment  the  supply 
wires,  called  the  mains,  should  be  carried  to  the 
central  distributing  points  (known  as  cut-out  or 
panel  equipments),  there  being  one  such  main  for 
each  class  of  equipment  that  is  separately  metered 
(see  Art.  4).  These  mains  are  carried  to  all  panel 
equipments  controlling  the  class  of  appliance  which 
the  mains  are  intended  to  supply.  The  branch  cir- 
cuits which  run  to  light  and  power  outlets  and  to 

162 


the  vario'us  appliances  radiating  from  these  panel 
equipments,  should  be  located  in  central  and  ac- 
cessible positions.  (To  find  the  proper  size  of  wires 
for  carrying  any  current  any  distance  for  any  num- 
ber of  lamps,  or  their  equivalent,  at  any  loss  of 
voltage,  see  table  and  examples  on  pages  69  to  78.) 
Distributing  Panels. 

Art.  8:  In  residence  work  it  is  good  practice  to 
place  the  distributing  panels  in  cellars,  servants' 
halls  or  corridors  (not  in  clothes  closets)  so  that 
workmen  can  get  to  them  when  necessary  without 
disturbing  the  occupants  of  the  house,  and  where 
possitffe  dirty  shoes  and  hands  will  do  the  least 
damage.  The  necessity,  however,  does  not  often 
occur  in  well  designed  and  installed  systems. 

These  panel  equipments  may  consist  of  groups 
of  porcelain  cut-outs  and  fuses  or  porcelain  base 
knife  switches  and  fuses.  In  the  best  class  of  work 
knife  switches  and  enclosed  fuses  are  mounted 
directly  in  two  vertical  rows  on  polished  slate  or 
marble  panels  and  cross  connected  by  metal  straps 
to  polished  copper  bus-bars  rising  up  the  middle 
of  the  panel.  These  bus-bars  are  fitted  at  their 
ends  with  lugs  to  which  the  mains  connect.  The 
cut-outs  or  panel  are  surrounded  with  slate  edg- 
ings containing  openings  through  which  the  circuit 
wires  pass  to  connect  to  the  branch  switches.  The 
slate  frame  thus  formed  is  mounted  in  a  metal  box 
with  from  three  to  four  inches  (3"  to  4")  space 
around  the  slate,  thus  forming  a  gutter  in  which 
the  circuit  wires  can  be  carried  from  the  ends  of 
the  conduits  terminating  in  the  metal  box,  to  the 
various  switches.  If  a  wooden  door  is  used  it 

153 


should  be  lined  with  slate  and  any  wood  trim  which 
covers  the  gutter  and  overlaps  the  joint  between 
the  box  and  wall  should  be  lined  on  the  under  sur- 
face covering  gutter  with  metal.  Where  metal  doors 
and  trims  are  used  only  the  slate  door  lining  is  re- 
quired. These  trims  are  usually  from  24  to  28 
inches  wide  and  of  varying  lengths  to  suit  the  num- 
ber of  circuits. 

Each  panel  circuit  or  switch  should  be  numbered 
by  means  of  a  metal  stamp  on  the  bus-bars  opposite 
the  switch  and  a  directory  sheet  should  be  placed 
on  the  inside  of  the  door  giving  the  number  of  each 
switch  and  the  number  and  location  of  the  lights 
controlled.  There  should  be  a  separate  double  pole 
cut-out  or  switch  and  fuses  for  each  circuit  con- 
suming 660  watts  or  less  in  the  case  of  lamps  or 
small  power  and  heating  devices;  and  a  similar 
cut-out  and  switch  for  each  outlet  for  motor,  etc., 
where  the  capacity  is  greater  than  300  or  350 
watts  (see  Art.  9),  (see  illustrations,  pp.  33-36). 

Where  more  than  one  main  feeds  a  panel  in  bus- 
bar construction,  the  bus-bars  are  cut  into  the  re- 
quired number  of  sections  and  each  section  carried 
out  between  switches  to  the  edge  of  the  panel  that 
the  main  wires  may  be  joined  to  the  bus-bar  ends 
just  inside  the  slate  edge  and  without  the  necessity 
of  having  the  wires  cross  the  panel. 

To  limit  the  necessity  of  cutting  away  too  much 
of  walls,  floors  and  supports,  where  circuit  conduits 
come  together,  the  number  of  circuits  at  any  panel 
box  should  be  limited  to  ten  or  twelve  by  placing 
as  many  boxes  at  separate  locations  as  may  be 
necessary  to  supply  the  residence.  Where  the  con- 

154 


struction  will*  permit,  however,  as  many  as  eighteen 
to  twenty-four  circuits  may  be  grouped  at  a  single 
panel  equipment  without  undue  size. 
Branch  Circuits. 

Art.  9:  The  rules  of  the  Fire  Underwriters  allow 
660  watts  distributed  at  sixteen  sockets  on  each 
2-wire  lighting  circuit.  It  is  recommended,  how- 
ever, that* the  number  of  sockets  be  limited  to 
twelve  or  thirteen  on  a  circuit,  as  this  does  not 
greatly  affect  the  cost  of  the  work  and  will  permit 
the  use  of  No.  14  wire  for  practically  all  such 
branch  circuits  without  undue  loss  in  voltage  and 
without  appreciable  variation  in  voltage  between 
outlets  on  the  same  circuit  under  any  condition  of 
use.  (See  Carrying  Capacity  of  Wires,  p.  68.) 

Branch  circuits  for  single  phase  power  are  also 
two-wire  and  vary  in  size  depending  on  the  horse- 
power of  the  motor  or  the  watts  of  the  appliance 
connected. 

In  wiring  for  small  motors  from  y2  H.P.  to  I 
HLP.  branch  circuits  should  be  No.  14  wire  for  220- 
volt  motors  and  No.  12  wire  for  no-volt  motors. 
These  sizes  are  made  necessary  because  of  the  large 
inrush  of  current  at  the  moment  of  starting  the  mo- 
tor. For  either  appliances  where  there  are  no  mov- 
ing parts  (such  as  electric  soldering  iron)  the  size  of 
the  wires  vary  with  the  watts  consumed,  but  in  no 
case  may  such  wires  be  smaller  than  No.  14  Brown 
and  Sharp  gauge  (see  p.  81,  5th  column).  Where 
heating  devices  are  of  small  capacity  (as  glue  pot 
and  soldering  iron  in  basement  workshop)  two  or 
more  may  be  placed  on  one  circuit.  Where  the  watt- 
age of  a  single  appliance  is  350  watts  or  more,  it  is 

155 


better  to  carry  a  separate  circuit  to  each  such  ap- 
pliance. 

The  branch  circuits  to  electric  cooking  ranges 
are  generally  three-wire;  the  size  depending  on  the 
capacity  of  the  range. 

The  branch  circuit  for  the  vacuum  cleaner  outlets 
should  be  on  the  power  section  of  the  system  and  as 
but  one  outlet  is  used  at  a  time,  all  the  vacuum 
cleaning  outlets  in  the  residence  may  be  placed  on 
one  No.  12  wire  branch  circuit  and  connected  for 
220  volts. 

Where  the  lighting  companies  make  separate 
rates  (as  in  Art.  4)  branch  circuits  to  lighting  ap- 
pliances— to  power  appliances — and  to  heating  ap- 
pliances must,  of  course,  be  kept  separate  and  con- 
nected to  the  proper  section  of  panel  equipments. 

Knob  Work  With  Flexible  Non-Metallic  Conduit. 

Art.  10:  In  frame  residence  with  stud  partitions, 
it  is  permissible  to  carry  wires  on  porcelain  insu- 
lators on  the  sides  of  the  beams  and  studs  and 
through  them  by  enclosing  in  porcelain  tubes  with 
flexible  non-metallic  conduit  (flexible  tube)  from 
nearest  knob  to  outlet,  keeping  the  wires  as  far  as 
possible  from  the  floor  or  ceiling  to  prevent  injury. 
Outlet  boxes  should  be  used  for  flush  switches  and 
receptacles;  but  for  ceiling  and  side  fixture  outlets 
where  there  are  no  gas  pipes  and  for  surface 
switches  and  receptacles,  wood  fixture  blocks 
should  be  built  into  the  walls  and  securely  fastened 
to  beams  and  studs  to  give  adequate  support  for 
the  fixtures  and  fittings.  This  type  of  construction 
is  known  as  "knob  and  tube"  work  and  is  not  only 

166 


the  cheapest  but  also  a  very  satisfactory  method  of 
installation  for  concealed  wiring  (see  pp.  91-92). 

Armored  Cable. 

Art.  loa:  Some  architects  and  engineers  specify 
armored  cable  for  frame  or  semi-frame  residences 
(pp.  91  and  101).  This  armored  cable  is  made  by 
wrapping  steel  tape  or  ribbon  around  the  two  or 
more  wires  of  the  mains  or  circuits,  thus  giving  a 
heavy  metal  sheathed  main  or  branch  circuit.  Such 
cable  is  made  in  lengths  of  from  50  to  250  feet. 
Armored  cable  may  be  laid  or  drawn  between  beams 
and  studs  or  furring  strips  with  practically  no  liabil- 
ity to  mechanical  injury  from  nails,  etc.  Armored 
cable  should  not  be  placed  in  brick  or  concrete  walls 
unless  imbedded  in  plaster-of-paris  or  other  suit- 
able material  to  protect  the  sheath  and  wires  from 
the  corrosive  action  of  the  surrounding  ingredients. 
For  the  same  reason  the  best  practice  prohibits  such 
armored  cable  being  placed  in  brick  or  concrete 
walls  where  subject  to  considerable  dampness.  Out- 
let boxes  in  this  construction  are  required  at  all 
outlets,  and  the  metal  armor  should  be  grounded 
as  called  for  in  Art.  6. 

Armored  cable  construction  is  very  satisfactory 
in  residences  where  the  permanent  decorations  are 
not  expensive  or  where  the  construction  is  such 
that  the  concealed  lengths  between  outlets  may  be 
withdrawn  and  new  lengths  drawn  in  (in  case  of 
trouble)  without  injury  to  the  finished  surface.  This 
construction  is  a  little  more  expensive  than  knob 
and  tube  work  (see  Art.  12). 

157 


Flexible  Steel  Conduit. 

Art.  lob:  Where  the  character  of  a  residence  is 
such  that  it  would  be  expensive  to  make  repairs  or 
alterations  in  the  concealed  wiring,  good  practice 
calls  for  the  use  of  concealed  conduits  for  the  re- 
ception of  the  wires.  These  conduits  should  be 
large  enough  to  permit  the  easy  drawing  in  and 
withdrawal  of  the  wires  without  the  use  of  tackle. 
The  smallest  conduit  generally  used  for  electric 
light  branch  work  is  about  %  inch  inside  diameter 
(see  p.  93).  Conduits  should  be  securely  fastened 
to  building  construction  and  have  easy  bends  to 
facilitate  the  drawing  in  of  the  wires.  Flexible 
steel  conduit  is  frequently  used  for  this  purpose, 
the  construction  of  which  is  practically  the  same 
as  armored  cable  but  in  larger  and  tube  form. 
These  flexible  conduits  are  made  in  lengths  of  from 
25  to  100  feet  for-  lighting  work  and  this  type  of 
wiring  installation  is  more  expensive  than  with 
armored  cable  (see  Art.  12). 

Rigid  Conduits. 

Art.  ice:  For  the  highest  class  of  residence  work, 
architects  and  engineers  generally  specify  rigid  con- 
duit construction  (see  p.  92).  These  rigid  conduits 
are  of  gas-pipe  thickness  and  are  coated  on  the  in- 
side with  a  tough  elastic  and  very  smooth  enamel. 
The  exterior  may  either  be  coated  with  the  same 
enamel  or  galvanized.  The  conduits  come  in  ten- 
foot  lengths  and  all  diameters  from  %-'mch  to 
6-inch  and  are  joined  by  means  of  screw  couplings 
of  the  same  material  and  the  joints  are  made  tight 
by  the  use  of  red  or  white  lead.  This  prevents  the 
entrance  of  any  moisture.  This  is  the  most  ex- 

158 


pensive   character  of  concealed  wiring  work    (see 
Art.   12). 

Wood  Moulding. 

Art.  lod:  This  class  of  work,  which  is  not  per- 
mitted in  concealed  places,  is  frequently  resorted 
to  on  account  of  the  cheapness  and  where  it  is  un- 
desirable, or.  unnecessary  for  appearance,  to  run 
circuits  inside  of  walls  or  ceilings.  Wood  moulding 
work  is  especially  adapted  to  the  cheaper  class  of 
cottages,  bungalows,  etc.  For  construction  rules 
se-e  page  88. 

Cleat  Work. 

Art.  loe :  In  dry  places  and  where  the  wires  are 
not  liable  to  mechanical  injury,  or  contact  with 
other  objects,  circuits  may  be  supported  on  porce- 
lain cleats  or  knobs. 

For  this  class  of  work  the  wires  should  be  sepa- 
rated, by  their  insulating  knobs  or  cleats,  two  and 
one-half  inches  from  each  other  and  at  least  one- 
half  inch  from  the  surface  wired  over  (pp.  68  and 
79),  where  the  voltage  does  not  exceed  300. 

Metal  Moulding. 

Art.  icf :  Where  it  becomes  necessary,  for  me- 
chanical reasons,  to  use  metal  moulding  the  sug- 
gestions given  on  pages  89  and  90  should  be  fol- 
lowed. 

Bell  Conduits. 

Art.  log:  Bell  and  telephone  cables  and  wires 
need  not  necessarily  be  in  conduit  nor  need  they 
be  installed  on  knobs.  In  fireproof  or  semi-fire- 
proof residences  where  the  cables  come  in  contact 
with  brick  or  concrete  and  would  not  last  and  in 
frame  residences  where  it  is  desired  to  make  re- 

159 


pairs  to  the  concealed  wiring  without  injury  to  the 
walls,  such  wires  should  be  placed  in  concealed 
conduits,  installed  in  the  same  manner  as  described 
above  for  electric  light  wiring.  In  the  best  class 
of  residence  work  this  is  usually  done. 

Conduit  Fittings. 

Art.  1 1  :  In  both  armored  cable  and  metallic 
conduit  construction  special  fittings  are  used  to 
connect  the  metal  to  the  outlet  box  or  cut-out  box. 
or  other  opening,  and  in  the  case  of  conduit  work 
these  bushings  and  nipples  are  so  designed  and  in- 
stalled that  the  wire  is  drawn  over  smooth  rounded 
surfaces  to  prevent  abrasion  of  the  braid  covering 
of  the  conductors  while  they  are  being  drawn  in 
(seep.  93). 

Approximate  Wiring  Costs. 
Art.   I2a:  Due  to  the  varied  cost  of  labor  and 
material  and  to  varying  methods  of  building  con- 
struction, universal  costs  of  electric  light  work  for 
the  several  types  of  wiring  hereinbefore  described, 
cannot  be  given,   but   for  the   purpose  of  general 
comparison  the   following  approximations   may  be 
a  help: — 
Knob  and   (Flexible)   Tube 

Work   $1.50  to  $2.50  per  outlet 

B.  X.  Cable  Work 2.00  to    5.00    !'       " 

Flexible     Steel     Conduit 

Work    3.50  to    5.50    "       " 

Rigid   Metallic  Conduit 

Work    4.00  to    7.00    "       " 

It  must  be  borne  in  mind,  however,  that  these 
proportions  for  the  wiring  work  will  not  follow 
as  proportions  for  the  complete  equipment,  as  the 

160 


cost  of  fixtures,  appliances  and  lamps,  etc.,  will  be 
the  same  for  any  one  of  the  systems,  and  as  these 
fixed  costs  are  generally  the  larger  part  of  the  com- 
plete total  the  above  proportions  would  apply  to 
perhaps  one-half  or  less  of  the  total  cost  of  any 
given  installation. 

Bell  Costs. 

Art.  i2b:  Bell  call  or  annunciator  requirements 
differ  for  almost  every  family  and  attempts  to  give 
costs  in  this  class  of  work  would  be  misleading.  In 
a  general  way,  however,  the  equipments  will  range 
from  $3.00  to  $10.00  per  call;  and  from  $1.50  to 
$8.00  per  extension  bell  or  annunciator  drop.  The 
smaller  costs  are  for  the  simpler  systems  with  con- 
cealed wires  not  in  conduits,  and  the  higher  costs 
for  more  or  less  complicated  call  systems  with 
wires  in  concealed  rigid  conduits. 

House  Telephone  Costs. 

Art.  i2c:  A  house  telephone  system  intercom- 
municating between  various  rooms  of  the  residence 
and  arranged  on  what  is  known  as  metallic  circuit 
connections  (to  prevent  cross-talk)  will  cost  from 
$20.00  to  $50.00  per  instrument,  depending  upon 
the  number  and  finish  of  the  instruments,  and 
whether  or  not  the  concealed  wire  is  in  conduit. 
Most  of  the  telephone  manufacturers  of  this  class 
of  instrument  make  a  standard  telephone  with  ten 
(10)  buttons,  thus  providing  for  intercommunica- 
tion between  eleven  (n)  points. 

Wire  for  Light  and  Power. 
Art.   i3a:  All  of  the  various  fire  underwriters 
organizations  require  "Rubber  Covered"  wire  (see 
p,  66)  for  all  classes  of  concealed  residence  wiring, 

161 


These  wires  may  have  a  single  impregnated  braid 
in  case  of  knob  and  tube  work  and  a  double  braid 
in  the  other  classes  of  concealed  work  hereinbe- 
fore described.  The  life  of  rubber  insulation  de- 
pends largely  upon  the  amount  of  pure  unreclaimed 
Para  rubber  used  in  the  insulating  compound  and 
the  method  of  applying  it  to  the  copper  conductor. 
The  very  best  class  used  in  residence  wiring  as  well 
as  the  most  expensive  contains  about  30  per  cent, 
pure  Para  rubber. 

In  installations  supplied  by  alternating  current 
it  is  important  that  all  the  wires  of  any  branch  cir- 
cuit, main  or  feeder  should  be  in  the  same  conduit. 
In  fact,  this  should  be  absolutely  insisted  upon  to 
prevent  trouble  from  induction  (see  p.  91).  Joints 
in  wires  should  not  be  allowed  where  they  will  be 
concealed  in  conduits  or  be  at  inaccessible  points. 
Where  splicing  is  necessary  the  joint  should  first  be 
made  mechanically  strong,  then  soldered  for  per- 
fect electrical  contact  and  insulated  with  rubber 
compound  and  tape  and  made  equal  in  insulation 
to  the  rest  of  the  wire  (see  p.  68). 

Bell  and  Telephone  Wire. 

Art.  i3b:  Wire  used  in  bell  and  telephone  systems 
may  be  of  the  same  quality  as  above  described  but 
need  not  be  as  large  in  size.  For  small  bell  sys- 
tems No.  18  B.  &  S.  gauge  is  amply  large  for  the 
section  wires  and  No!  16  for  the  battery  wires. 
These  sizes  are  determined  mainly  by  means  of 
mechanical  strength  and  in  order  to  easily  distin- 
guish between  battery  and  section  wire. 

Where  there  are  a  number  of  bell  or  telephone 
wires  carried  between  two  points  a  considerable 

163 


distance  apart,  it  is  quite  customary  to  buy  the 
cable  already  made  up  and  these  wires  are  often  as 
small  as  No.  20  or  No.  22  B.  &  S.  gauge.  The 
separate  wires  in  such  cables  may  be  insulated  with 
two  silk  and  one  cotton  wrapping  impregnated  with 
beeswax  to  keep  the  ends  of  the  yarns  from  un- 
raveling and  the  made-up  cable  encased  in  a  heavy 
fireproof  braided  covering. 

The  most  approved  type  of  house  telephone  con- 
tains two  wires  for  each  call,  two  wires  for  battery 
talking,  two  wires  for  battery  ringing.  Each  pair 
of  wires  should  be  twisted  to  prevent  "cross-talk." 
This  refers  to  metallic  circuit  connections  in  house 
intercommunicating  telephone  systems.  Where  silk 
and  cotton  cables  are  used  in  damp  places  the  cable 
should  be  encased  in  lead  to  prevent  moisture  de- 
veloping short  circuits  between  the  various  wires. 
Voltage  Loss  in  Conductors. 

Art.  14:  The  size  of  conductors  given  in  the  Na- 
tional Electrical  Code  for  any  given  current  is  based 
only  on  the  safe  carrying  capacity  (see  table,  p.  81) 
without  undue  heating  and  does  not  necessarily  de- 
termine, except  where  the  distance  is  short,  the 
size  of  conductor  that  good  engineering  practice 
requires.  The  proper  size  of  conductors  in  any 
installation  should  be  determined  by  the  loss  in 
volts  between  the  service  supply  -\nd  the  furthest 
outlet  or  appliance  (ekctrically  speaking)  when 
the  entire  equipment  is  in  simultaneous  operation. 
In  residence  work  2  per  cent,  loss  between  the 
above  mentioned  points  is  not  excessive  (see  pp. 
69-78).  Conductors  smaller  than  No.  14  Brown 
and  Sharp  gauge  must  never  be  used  in  electric 

16? 


light  work,  except  inside  the  lighting  fixtures  where 
a  smaller  conductor  is  permissible. 

In  proportioning  the  total  voltage  losses  of  a 
residence  installation  between  the  mains  and  branch 
circuits  not  more  than  I  per  cent,  loss  should  be 
permitted  in  the  branch  circuit  panel.  A  simple 
table,  with  examples  worked  out,  to  show  its  use, 
is  given  on  pages  69  to  78.  By  its  use  the  proper 
size  of  wire  is  easily  determined  for  carrying  any 
current  any  distance  at  any  desired  loss  in  volts. 

There  is  a  large  rush  of  current  at  the  moment 
of  starting  up  single  phase  alternating  current  mo- 
tors and  the  loss  in  such  wires  should  be  based  on 
this  momentary  large  amount  which  may  vary  from 
100  to  200  per  cent,  overload  of  current.  If  this 
condition  is  not  provided  for  it  is  quite  possible  to 
install  wires  that  would  be  large  enough  to  operate 
the  motor  after  it  is  in  motion,  but  too  small  to  take 
care  of  this  starting  current  (see  pp.  22-32). 

Room  Switches. 

Art.  i5a:  A  liberal  use  of  switches  in  a  residence 
invites  economy  by  encouraging  the  putting  out  of 
lights  when  leaving  rooms.  They  soon  pay  for 
themselves.  The  most  satisfactory  switches  are  of 
the  flush  type  and  should  be  placed  in  metal  cut- 
out boxes  sunk  in  the  wall  and  should  generally  be 
located  just  inside  of  entrance  doors. 

Large  rooms  with  numerous  outlets  should  be 
controlled  by  more  than  one  switch,  and  in  long 
living  rooms  it  is  often  a  good  plan  to  place  the 
lights  of  each  end  of  the  room  on  a  different  switch 
control,  both  for  convenience  of  occupants  and 
economy  in  bills. 

164 


For  electroliers,  switches  are  sometimes  used,  so 
designed  that  one  turn  of  the  handle  lights  one 
group  of  lights;  the  second  turn  lighting  an  addi- 
tional group  without  putting  out  the  first  group, 
and  a  third  turn  will  put  all  out. 

Servants'  rooms  should  have  switches  and  high 
fixtures  not  only  so  that  the  lights  will  be  more 
apt  to  be  extinguished  when  not  needed,  but  also 
to  prevent  the  use  of  fixtures  as  clothes  hangers. 
Hall  Switches. 

Art.  I5b:  For  hall  and  stairs  it  is  customary  to 
arrange  lights  that  they  may  be  turned  on  or  off 
frqni  any  one  of  several  switches  known  as  3-way 
and  4-way  switches.  A  light  in  first  floor  hall  and 
one  on  the  second  floor  may  be  controlled  by  a 
switch  at  entrance  door  and  also  controlled  from 
second  floor.  In  the  same  manner  an  outlet  on 
third  floor  may  be  controlled  by  a  switch  in  second 
hall  and  one  on  third  floor.  This  allows  a  person 
going  to  the  third  floor  to  come  in  late,  light  halls 
and  stairs  to  room  and  put  out  lights  again  from 
above  and  thus  do  away  with  wasteful  burning  (see 
Hall  Wiring,  p.  166). 

The  three-way  arrangement  for  servants'  stairs 
especially  will  keep  down  the  monthly  bills,  because 
of  the  ease  with  which  the  servants  can  put  out 
lights.  Sometimes  this  3-way  switch  arrangement 
is  used  in  bedrooms,  one  switch  at  door  and  the 
other  at  bed. 

Master  Switch. 

Art.  i5c:  A  master  switch  may  be  placed  in  the 
owner's  bedroom  and  so  connected  that  the  switch 
will  control  the  first,  second  and  third  floors,  main 

165 


hall  and  stairs,  3-way  lights,  either  independent  of 
whether  the  local  switches  have  been  used  or  not 
(see  Master  Bedroom,  p.  167). 


J  L 


3- Way  Switch 
for  lighting 
Fixture  A  in 
Living  Room 5- 
froni  either 
side  of  entrance 

-T°—  \ 
Living  Room   \ 


\ 

(3-  Way  Switch\ 
at  head  of 
Stairs  for 

s 

lighting  Fixture  A) 

-s3 

Incfa 

A 

Newel  Po 
Outlet  fo 
(descent  I 
50  Wat) 
'equivalei 

|Up 

jj        1 

^2                S:if 
amps 
(.The  \lf 
it                also  be 

3-Way  Switch  for 
lighting  Fixture  at 
head  of  Stairs 
jhting  Fixture  should 
be  controlled  by  :5-Way 
Switch  at  head  of  Stairs) 


Lighting  of  Fixture 
controlled  by  3-Way 
Switch  at  head  of 
Stairs  and  by  3-Way 
Switch  at  E 


Ceiling  Outlet  for 
2  Incandescent  Lamps  To 
Watt  eacli  equivalent 


Dinin 


-S3 

3-Way  Switch 
for  lighting 
Fixture  A  in 
Dining  Room 


VESTIBU 


./        Light  ing  of 
''Fixture  6  controlled 
by  3-Way  Switch 
at  E  and  by  3-  Way 
Switch  at  F 


Lighting  of  Fixture  C 
controlled  by  3-Way  Switch 
at  F  and  by  3-Way  Switch  at  G 


S?G    DD     Push  to 

Kitchen  Annunciator 


ENTRANCE 

Closet  Switches. 

Art.  i5d:  Closet  switches  are  often  controlled  by 
switches   set   in   the   door  jambs   and   operated   by 

166 


movement  of  door.  As  closets,  however,  are  often 
left  open  for  ventilation,  wall  switches  are  pref- 
erable (see  cut  of  closet  below). 

Pilot  Switches. 

Art.  156:  With  switches  operating  lights  hot  visi- 
ble  from   the   switch    (as   in   case  of   cellar)    it   is 


1=--==! 

^                  =\ 

-®SeeB 

Outlet  for    LJ 
D«sk  Lamp           Y£< 

b  ^ 

See  B  -ji- 

\  ^^   LJ  . 

MASTER  E 

ED    ROOM 

>T<SeeB 

i    >r<    n 

4  Interior  Telephone 

4  Public  Telephone 
Extension 

i       Bracket  Outlet  for  2 
\       Incandescent  I^amps 
\      50  Watt  each  equivalent 

Outlet  for  Ozonizer,  i—  1_ 
Vibrator,  Vacuum     l—T 
Cleaner 

Ceiling 
Outlet  for 
Closet  Lamp 

Special  Heating  Outlet  for 
Water  Heat  >r,  Heating 
1'ad,  Radiator    1 

,_.~\\     /    Push  to  Bell  in 
CLOSET         \\       Servants'  Quarters 
S.P.Switch  for    oW                                  \ 
CloS^PrT®?J^erSwitch^ 

1   1  .    X.          SM  Q 

Outlet  for                           / 
Bed  Reading                      / 
Lamp  \                         /    Y~>( 

3- Way  Switch  for  lighting  Fixture  B 
from  either  Sidt-  of  Enti.incc 


economical  to  equip  the  switch  with  a  small  pilot 
light  which  burns  when  switch  is  in  use. 

This  same  style  of  pilot  switch  should  be  used 
in  connection  with  all  heating  or  other  appliances 
which  are  fixed  in  position  and  do  not  visibly  indi- 
cate when  current  is  on  (see  Art.  18). 


Motor  Switches. 

Art.   16:     Fused  knife  switches 

1G7 


(see  p.   TT2)   in 


metal  boxes  should  be  used  in  connection  with 
A.  C.  motors  of  y*.  H.P.  and  larger.  These  switches 
should  be  double  pole  and  located  near  the  motor 
they  control.  Motor  starting  boxes  are  sometimes 
used  with  ^  H.P.  to  i  H.P.  A.  C.  single  phase 
motors  in  order  to  cut  down  the  momentary  rush 
of  current  (described  in  Art.  14),  but  nearly  every 
service  company  will  permit  motors  to  be  operated 
directly  from  the  switch.  Small  motors  may  be 
operated  from  flush  switches  of  room  type. 

Tank  Switches. 

Art.  17 :  When  the  house  water  tank  in  the  attic 
is  filled  by  an  electric  pump,  a  switch  should  be 
placed  at  the  tank  and  connected  to  a  float  in  the 
water,  and  so  wired  and  connected  as  to  automat- 
ically start  and  stop  the  pump  by  the  fall  and  rise 
of  the  water  in  the  tank. 

Combination  Pilot  Switch  and  Receptacle. 

Art.  18 :  Where  portable  electrical  appliances  do 
not  visibly  indicate  when  the  current  is  on,  and 
where  such  appliances  are  connected  by  means  of 
flexible  wires,  the  wall  outfit  should  consist  of  a 
switch  pilot  light  and  receptacle.  All  three  (3)  may 
be  placed  in  the  same  outlet  box  and  one  (i)  plate 
covers  all. 

Base  Receptacles. 

Art.  ipa:  Flush  receptacles  and  plugs  should  be 
liberally  distributed  throughout  the  residence  as 
they  are  very  handy  for  a  great  variety  of  purposes 
and  may  be  generally  placed  on  or  just  above  the 
baseboard.  The  plates  may  be  painted  to  match 
surroundings  and  made  very  inconspicuous. 

Receptacles   for  the  same  voltage  and  class  of 

168 


I  hi  Kb 


Bell 

Transformer  or 
1 1  Battery  Outlet 


CELLAR 


Ceiling  Outlet  for  2 
Incandescent  Lamps 
50  Watt  each  equivalent 


Special  Power-Current  Outlet 
(Wall  Receptacle)  for    -\ 
Workshop  Machinery         ^ 


Lathe 


See  A 


I — I 

^-§   S.P.  Switch  at  Head  of  Stairs 
for  lighting  Fixture  A 

Ceiling  Outlet 


Furnace 


service  should  have  interchangeable  plugs  to  avoid 
the  necessity  of  changing  the  plug  on  the  flexible 


160 


cord  attached  to  any  lamp  or  appliance  should  its 
location  he  changed. 

Receptacles,  however,  should  be  so  designed  that 


Ceiling  Outlet  for  2 
Incandescent  Lamps 
50  Watt  each  equivalent 


irculation  Heater 
Special  Heating  Outlet  for 
Electric  Range  or  'Oven 
Broiler,  Hot  Disc  Stove 

3- Way  Switch  for 
controlling  Fixture  C 
ither  G  or  H 


See  B 


ial  Power- Current  Outlet 
for  small  Motor  or  Power    (ft. 
Table.  -    W 

Power  Table  Accessories, 

Ice  Cream  Freezer, 
Coffee  Grinder,  Metal  Polisher, 

Bread  Mixer,  Egg  Beater, 
Knife  Sharpener,  Meat  Chopper 


170 


the  plugs  on  apparatus  of  different  voltage  or  class 
cannot  be  inadvertently  connected  to  wrong  recep- 
tacles. This  may  be  accomplished  by  using  the 
same  make  of  receptacle  with  different  openings 
for  each  voltage  or  class  or  by  specifying  a  differ- 
ent make  for  each  class.  If  this  is  not  done,  a  110- 
volt  appliance  might  be  easily  connected  to  a  220- 


Outlet  for  Cigar  Lighter, 
Reading  Lamp 


Bracket  Outlet  for  2 
Incandescent  Lumps 
50  Watt  each  equivalent 


LIBRARY 


See  B 


Ceiling  Outlet  for  4 
Incandescent  Lamps 
50  Watt  each  equivalent 


Outlet  for       |_ 
Vacuum  Cleaner 


S:P.  Switch  for 
lighting  Fixture  A 


volt  receptacle  in  which  case  the  appliance  would 
probably  be  destroyed  to  say  nothing  of  the  fire 
hazard  involved. 

Receptacles  for  lighting  purposes  are  usually  no 
volts. 

In  addition  to  the  lighting  receptacles  which  are 
usually  installed  for  reading  lamps,  piano  lamps, 
etc.,  there  should  be  one  or  two  spare  receptacles 

1  171 


in  each  main  room  and  hall.  One  of  the  receptacles 
in  main  living  room  or  hall  should  be  placed  so  as 
to  be  near  a  suitable  location  for  a  Christmas  tree, 
so  that  this  may  be  illuminated  without  unsightly 
wires  showing  in  the  room. 

A  porcelain  lamp  receptacle,  mounted  in  a  con- 
dulet   or   outlet   box,    is    often    placed  under    the 


1    "fT                  R  YZ^\  Bracket  Outlet  for  2                   X^<  s      a 
Outlet  for            *~*  Incandescent  Lamps                  XlX 
H  Piano  Player,                5°  Watt  «"sh  equivalent 
Vacuum  Cleaner 

Special  Floor  Outlet  /g 
for  Heating  and      vR 
Cooking 

)       P-,       Table  Bell  Push  to                     
L^-l    Kitchen  Annunciator            rJJ 

LIVING  ROOM 


Outlet  for  Moving  Picture 
Lamp,  Tea  Table,  Toaster, 
Tea  Pot,  Coffee  Percolator 


A 

VV  Ceiling  Outlet  for  _ 
fij  Incandescent  Lamps 
*-*  50  Watt  each  equiva- 
lent 


Outlet  for  Tan,  Cigar 
/Lighter,  Portable 
/        Lamp,  etc. 

I 


S*  3- Way  Switch  for  lighting 
.Fixture  A  from  either 
Side  of  Entrance 

kitchen  range-hood  and  the  conduit  run  around 
under  the  hood  to  the  side  wall  where  the  control- 
ling switch  is  located. 

Outdoor  Decoration  Receptacles. 

Art.  igb:  A  waterproof  receptacle  and  plug 
should  be  located  outside  the  main  entrance,  con- 
trolled by  a  switch  in  hall  for  step  and  walk  canr 
opy  lighting. 

179 


A  similar  receptacle  and  plug  may  be  placed  high 
up  on  pillar  or  wall  of  porch  for  electric  decora- 
tions. These  receptacles  should  be  on  a  separate 
circuit  from  panel  and  controlled  by  a  switch  at 
porch  door. 


To  Pantry  3_Way  Switeh  Outiet  for  lighting 

|    _--"~'b  Fixture  B  in  Pantry 


1<^"             | 

^~"~"~1"--  Yv\  S3  3-  Way  Switch 
^*   \   for  lighting  Fi 
See  B  \ 

1    i       \ 

Outlet             npS  B 
xture  A          ^—  X 
Bracket  Outlet  for  2 
Incandescent  Lamps 
50  Watt  each  equivalent 

Special  Flooi  Outlet 
/for  Electric  Cooking 
r    Toaster,  Egg  Boiler, 
C^\  Chafing  Dish,  Percolator 

m     Table  Bell  Push  to 
'—  '    Kitchen  Annunciator 
Ceiling  Outlet  for  i 
Incandescent  Lamps 
50  Watt  each  equivalent 

\  ROOM 

\                   Special  Outlet  for 
\                     Heater,  Fan, 
\              Vacuum  Cleaner, 

\rtsjTv 

Dutlet  for  O  (  X^X  B      ^ 

1                                   \ 

•U-   Serving  1 

_bi    Outlet  for  Elec.                          ?7\ 
"l±J      Serving  Tray,                               >>_X 
Drjnk  Mixer                                    v 
Table    j                                                  ^ 

DININb 

See  B 
K)       3-  Way  Switch  ( 

'                                                           Push  to  Annunciator   r^~i 
in  Kitchen            L-J 

Porch  Receptacles. 

Art.  IQC:  The  living  porch  should  have  one  or 
more  flush  wall  receptacles  placed  in  the  side  wall 
twelve  or  fifteen  inches  above  the  floor  (to  prevent 
water  splashing  on  them).  These  receptacles  for 
use  of  reading  lamp,  chafing-dish,  percolator,  etc. 

Bedroom  porches  may  have  a  similar  receptacle 
for  reading  light. 

Servants'  or  kitchen  porches  should  have  a  re- 

171 


ceptacle  pilot  light  and  switch  (see  Art.  18),  so  that 
ironing  may  be  done  on  the  porch  in  hot  weather. 
Should  a  receptacle  should  be  on  a  separate  circuit. 

Mantel  Receptacles. 

Art.  igd :  Receptacles  for  mantel  candles  may  be 
placed  in  the  wall  just  above  the  shelf,  or,  where 
the  design  will  permit,  in  the  shelf  itself.  These 


J  L 


Ceiling  Outlet  for  2 
Incandescent  La 
50  Watt  eac 
equivalent 


— i  Outlet  for  Plate  Oven, 
£1         Hot  Disc  Stove 


PANTRY  Outletfor 

Water  Sterili" 


p3x~x  .^ 
(V)  B 
^-A 


s°- 


Plate  Oven 


t  Disc  Stove 

Cf 


3- Way  Switch 
for  lighting 
Fixture  B 

To      _+ 
Dining  Room 


Bracket  Outlet  for  2 
Incandescent  Lamps 
00  Watt  each  equivaU 


Outlet  for  Vibrator, 

Ha:r  Dryer,  Shaving 

Mirror,  Elec.  Bath 

Cabinet 


receptacles  should  be  controlled  by  a  switch  at  con- 
venient location. 

Bed  Receptacles. 

Art.  196 :  Two  receptacles,  one  for  reading  lamp 
and  one  for  heating  pad  or  similar  sick  room  appli- 
ance, should  be  placed  at  the  side  of  each  bed  and 
connected  to  no-volt  lighting  circuit. ,  These  may 
both  be  in  the  same  outlet  box  and  covered  with  one 
plate.  Alongside  of  this  equipment  but  not  in  con- 

174 


tact  with  same,  may  be  placed  a  bell  receptacle  with 
removable  portable  cord  and  hand  "pear  push"  for 
bell  call.  This  bell  receptacle  and  plug  must  be  of 
entirely  different  design  from  the  two  before  men- 
tioned so  that  by  no  possibility  may  the  bell  plug  be 
attached  to  either  of  the  other  receptacles.  These 
bell  portables  are  connected  to  the  same  bell  wires 
as  the  wall  push  button  at  door,  so  that  either  point 


Vacuum  Cleaner 
<0  See  B 


Bracket  Outlet  for  3 
Incandescent  Lamps     (/* 
50  Watt  each  equivalent 


SEWING  ROOM 


i       Outlet  for 
-m    Fan, Iron 


Ceiling  Outlet  for  3 
Incandescent  Lamps 
50  Watt  each  equivalent 


S.P.  Switch  Push  to 

for  lighting  Kitchen 

Fixture  A         (S       Q]  Annunciator 


rings  the  same  bell  or  drop  on  the  annunciator. 

Floor  Receptacles. 

Art.  igi :  Where  receptacle  outlets  come  in  the 
floor,  they  should  be  placed  in  specially  designed 
floor  boxes  which  have  cone  shaped  tops  projecting 
above  the  floor  to  prevent  water  entering  the  box 
and  to  protect  the  wires.  When  these  portables  are 
not  in  use,  the  cone  top  can  be  removed  and  a  flush 
top  substituted. 

175 


Stereopticon  Receptacles. 

Art.  20 :  Stereopticon  and  moving  picture  ma- 
chines are  now  made  for  home  use.  The  recep- 
tacles for  some  have  a  larger  capacity  than  those  for 
lighting  and  are  usually  placed  at  the  end  of  the 
long  living  room  or  hall.  They  should  be  connected 
to  i  lo-volt  power  and  by  means  of  two  No.  8  wires. 

Vacuum  Cleaner  Receptacles. 
Art.  21 :  Flush  receptacles  ftfr  portable  vacuum 
cleaners  should  be  so  located  that  the  thirty  to  fifty 
feet  (30  to  50')  of  cord  that  goes  with  the  cleaner 
will  enable  the  operator  to  reach  all  parts  of  the 
house.  They  should  be  so  arranged  that  the  plugs 
are  not  interchangeable,  except  for  the  very  small 
type  as  explained  in  Art.  ipa.  The  momentary 
rush  of  current  with  many  of  the  larger  portable 
vacuum  cleaners  would  blow  the  fuses  of  small  cir- 
cuits and  it  is  advisable  to  put  these  receptacles  on 
a  separate  No.  12  wire,  and  as  but  one  point  is  used 
at  a  time,  all  the  vacuum  cleaner  receptacles  in  the 
residence  may  be  placed  on  the  same  circuit. 

Dining  Room  Special  Front  Outlet. 

Art.  22 :  There  should  be  a  receptacle  and  outlet 
box  placed  in  the  floor  under  the  dining-room  table, 
a  little  off  the  center,  so  as  to  clear  the  center  leg  of 
table.  This  should  be  fitted  with  a  removable  plug 
connected  to  permanent  table  wiring  (which  is  car- 
ried up  the  center  leg  of  the  table  along  the  under 
framework  and  out  on  the  crossbars,  where  the  wir- 
ing should  terminate  in  three  no-volt  fused  power 
receptacles.  One  of  these  may  be  used  for  electric 
chafing-dish  or  egg  boiler,  one  for  electric  toaster 
and  one  for  electric  coffee  percolator.  This  enables 

176 


the  housewife  to  use  the  above  appliances  and  dis- 
connect and  remove  them  as  desired,  without  reach- 
ing to  the  floor  and  with  practically  no  exposed 
connections,  -except  the  short  ones  over  the  edge  of 
the  table.  The  three  receptacles  under  the  edge  of 
the  table  may,  if  desired,  be  mounted  in  a  neat  box 
to  match  the  woodwork.  (See  Dining  Room,  p  173.) 

Other  Power  Receptacles. 

Art.  23 :  Flush  receptacles  for  power  and  heating 
appliances  are  of  sizes  depending  on  capacity,  but 
for  most  residence  work,  the  standard  10  ampere 
receptacle  and  plug  manufactured  by  many  com- 
panies, is  satisfactory  in  the  great  majority  of  cases. 
For  different  classes  of  apparatus  and  voltage,  these 
receptacles  should  not  be  interchangeable  (see  Art. 
I9a).  For  use  with  heating  or  similar  appliances, 
they  should  be  in  connection  with  pilot  lights  and 
switches,  as  explained  in  Art.  18.  This  type  of 
cortibined  switch  and  receptacle  should  be  used  for 
laundry  and  pressing  irons  (and  provision  should 
be  made  at  ironing  table  to  hold  up  the  cord  con- 
necting the  iron).  A  laundry  iron  receptacle  should 
always  be  placed  to  the  right  of  the  laundress. 

Cellar  Lighting. 

Art.  24:  Usually  10  or  15  watt  lamps  are  suf- 
ficient for  cellar  lighting  except  in  case  of  work 
bench  or  lathe,  which  should  be  brightly  lighted  by 
25  watt  or  40  watt  lamps. 

Outlets  should  be  so  located  as  to  illuminate 
sinks,  furnaces  and  any  pumps  or  apparatus  that 
need  attention.  Store  rooms  and  vegetable  rooms 
should  be  well  lighted  from  ceiling  with  controlling 
switch  at  door.  The  wine  room  switch  should  pref- 

177 


erably  be  placed  outside  the  door,  so  that  the  room 
may  be  inspected  through  glass  or  grating  of  door 
without  unlocking. 

There  should  be  at  least  one  outlet  in  cellar  con- 
trolled by  pilot  switch  at  the  head  of  the  stairs 
(see  Art.  156),  and  where  there  are  few  lights  in 
the  cellar  it  is  sometimes  advisable  to  put  all  on 
such  a  swritch.  (See  Cellar,  p.  169.) 
Porch  Lighting. 

Art.  25 :  Porches  are  usually  lighted  from  ceil- 
ing outlets  controlled  by  a  switch  at  porch  door 
with  receptacles  for  reading  lamps,  etc.  (See  Art. 
IQC.  (See  Porch,  p.  170.) 

Room  Lighting. 

Art.  26:  In  addition  to  mantel  lights  (see  Art. 
ipd),  side  or  ceiling  lighting  should  be  so  designed 
as  to  properly  illuminate  all  portions  of  a  room 
(see  pages  114-119),  in  such  a  manner  as  to  allow 
the  shifting  of  furniture  from  time  to  time  without 
destroying  the  harmony  of  the  interior.  For  this 
reason  residence  outlets  should  not  be  limited  to 
the  fewest  possible  permissible  with  the  original 
furniture  layout,  but  should  be  planned  with  a  view 
of  any  re-arrangement  of  furnishings.  Outlets  not 
needed  with  first  scheme  may  be  capped  until  re- 
quired. For  economy  as  well  as  for  convenience, 
room  lighting  should  be  controlled  by  switches  (see 
Art.  I5a).  Most  rooms  require  one  or  more  recep- 
tacles for  portable  lights  (Art.  19). 

A  cigar  lighter  may  be  placed  on  the  lighting  cir- 
cuit of  den  or  living  room.  It  uses  very  little  cur- 
rent and  does  away  with  burnt  matches.  It  needs 
no  switch  beyond  the  self-contained  one. 

178 


Dining  room — the  table  should  be  well  lighted  by 
ceiling  domes  or  showers. 

For  bedrooms,  in  addition  to  the  above  room 
lighting,  there  should  be  a  receptacle  for  desk  lamp 
and  there  should  also  be  a  reading  lamp  at  bed. 
(See  Art.  196.) 

Hall  Lighting. 

Art.  27 :  Halls  require  a  soft  general  illumina- 
tion and  the  addition  of  portable  table  and  vase 
lights  is  often  advantageous.  In  addition  to  the 
wall  switches  for  the  regular  lights,  there  should 
be  up  and  down  control  between  floors  as  mentioned 
in  Art.  i5b.  (See  Hall,  p.  166.) 

Pantry  Lighting. 

Art.  28:  The  pantry  should  be  well  lighted 
from  a  high  center  outlet  so  that  contents  of  dress- 
ers and  cupboards  may  easily  be  seen  and  this  out- 
let should  be  controlled  by  a  switch.  (See  Pantry, 
p.  174.) 

Kitchen  Lighting. 

Art.  29 :  Kitchens  are  generally  lighted  from 
ceiling  outlet  controlled  by  switch  at  door.  When, 
however,  there  are  appliances  around  side  wall  at 
which  the  cook  works,  there  would  be  a  shadow 
if  only  the  center  fixtures  were  used,  and  side  out- 
lets should  be  added  at  such  points  and  at  the  sink. 
The  range-hood  should  have  a  light  under  same,  as 
detailed  in  Art.  193.  (See  Kitchen,  p.  170.) 

Laundry  Lighting. 

Art.  30 :  Laundries  are  usually  finished  in  light 
color  and  need  comparatively  little  general  illumina- 
tion from  ceiling  fixture  controlled  by  a  switch  at 
door.  A  drop  light  should  be  provided  at  ironing 

179 


table  and  a  side  light  at  laundry  machine.     (See 
Laundry,  p.  170.) 

Bath  Room  Lighting. 

Art.  31 :  Most  bath  rooms  may  be  well  lighted  by 
means  of  a  2-light  ceiling  fixture  or  side  outlets 
placed  over  the  mirror,  the  fixtures  projecting  8  to 
15  inches  from  wall  and  with  two  inverted  lights 
in  such  position  as  to  light  top  of  head  and  each  side 
of  face,  controlled  by  a  switch  at  door.  Bath  room 
lights  should  never  be  so  placed  as  to  throw  the 
shadow  of  anyone  in  the  room  on  the  window 
shade.  (See  Bath  Room,  p.  174.) 

Sewing  Room  Lighting. 

Art.  32 :  The  general  illumination  of  the  sewing 
room  may  be  from  the  ceiling  with  switch  control. 
Side  lights  should  be  installed  to  brightly  illuminate 
the  sewing  machine  and  cutting  table  and  also  the 
chair  used  for  hand  sewing.  An  outlet  for  electric 
pressing  iron  (see  Art.  32),  should  be  installed  and 
when  the  room  is  used  in  hot  weather  an  electric  fan 
adds  to  comfort.  An  8-inch  fan  takes  very  lit- 
tle current — 20  to  40  watts,  and  can  be  used  on  lamp 
socket.  (See  Sewing  Room,  p.  175.) 

Closet  Lighting. 

Art.  33:  Closet  lights  are  desirable  unless  room 
fixtures  are  so  placed  as  to  illuminate  them.  Es- 
pecially is  this  true  of  storage  and  servants'  closets 
as  it  insures  cleanliness.  Closet  lights  should  be 
controlled  by  wall  or  door  switches.  (See  Art. 
I5d.)  (See  Closet,  p.  167.) 

Play  Room  Lighting. 

Art.  34 :  The  play  room  should  be  brightly  lighted 
from  the  ceiling  and  controlled  by  a  switch  at  door. 

180 


This  will  prevent  accidents  to  or  from  low  side  fix- 
tures. The  play  room  should  also  be  wired  for  use 
as  a  bedroom  with  side  lights  and  receptacles  with 
outlets  capped  up  for  future  use.  If  receptacles  for 
play  toys  are  installed  they  should  be  of  such  a 
character  as  not  to  permit  the  toys  being  connected 
to  other  outlets. 

Servant  Room  Lighting. 

Art.  35 :  It  pays  to  light  servants'  room  from 
high  ceiling  lights  designed  for  wide  distribution  of 
lighting  and  install  switch  at  door  for  control  of 
same.  The  lights  will  be  thus  used  more  econom- 
ically and  the  fixtures  cannot  be  carelessly  mis- 
handled. 

Workshop  Lathe. 

Art.  36:  Many  owners  like  to  provide  a  small 
workshop  for  their  own  use.  A  small  wood  turn- 
ing lathe  can  be  operated  by  a  motor  consuming 
about  200  watts.  This  lathe  may  be  controlled  by 
either  a  motor  starter  and  switch,  or  by  means  of  a 
switch  only,  as  detailed  in  Art.  16.  (See  Cellar,  p. 

i69.) 

House  Pump. 

Art.  37 :  Where  city  water  supply  is  not  available 
and  a  well  is  used,  a  tank  located  on  roof  or  attic  can 
be  filled  by  electric  pump.  The  well  pipe  may  be 
from  i  ^2-inch  diameter  up,  depending  on  the  quan- 
tity of  water  needed.  The  motor  may  be  controlled 
by  hand  or  it  may  be  automatic  in  action,  as  noted 
in  Art.  17.  (See  Cellar,  p.  169.) 

If  wiring  is  installed  a  double  throw  switch  is 
usually  placed  in  the  basement  or  at  the  pump  to 
permit  hand  operation  so  that  tests  may  be  made 

181 


from  time  to  time  to  see  that  everything  is  working 
satisfactorily.  Water  cocks  may  be  placed  around 
the  lawn  and  water  pumped  through  them  directly 
for  watering  lawn,  or  for  fire  purposes  without  us- 
ing up  the  water  in  the  tank. 

Refrigeration. 

Art.  38:  Where  ice  is  expensive  or  difficult  to 
obtain,  an  ice  box  refrigerator  electrically  operated 
can  be  installed.  These  outfits  require  little  atten- 
tion and  in  addition  to  keeping  the  box  cool,  can  be 
used  to  make  a  small  amount  of  ice  for  table  and 
sick  room  use. 

Stereopticon. 

Art.  39 :  Stereopticon  and  moving  picture  ma- 
chines are  now  made  for  residence  use  and  are  fast 
becoming  an  important  part  of  the  equipment  of 
every  home,  especially  where  there  are  young  peo- 
ple. Special  receptacle  should  be  provided  as  de- 
tailed in  Art.  20. 

Vacuum  Cleaner. 

Art.  40 :  Portable  vacuum  cleaners  are  well 
known  and  much  used.  They  should  not  be  con- 
nected to  the  branch  circuits  feeding  lights  and 
small  appliances  (see  Art.  9),  but  should  be  pro- 
vided with  a  special  circuit  and  their  own  outlets. 
(See  Art.  21.)  Sometimes  a  permanent  machine 
is  installed  in  the  basement  with  pipes  carried  con- 
cealed in  the  walls  and  with  convenient  outlets  on 
each  floor  to  which  hose  may  be  attached.  In  such 
a  case  it  is  advisable  to  place  near  the  motor  an  au- 
tomatic distant  control  switch  and  carry  one  No.  14 
wire  branch  circuit  to  flush  receptacles  placed  close 
to  each  hose  outlet.  The  plug  is  attached  to  the 

182 


end  of  the  hose  with  a  small  chain.  The  connections 
are  such  that  when  the  hose  is  in  use  and  the  plug 
inserted  into  the  receptacle,  the  cleaner  will  start 
up  and  when  the  hose  is  removed  thus  pulling  out 
the  receptacle  plug  the  motor  stops,  preventing 
waste  of  current.  The  receptacles  that  are  used  for 
connection  to  portable  machines  and  their  circuit 
are  not  used  in  this  case. 

Plate  Warmer. 

Art.  41  :  Plate  warmers  are  very  convenient  and 
add  much  to  the  ease  of  service  and  success  of  din- 
ners. They  may  be  placed  under  dressers  or  pantry 
table  and  should  be  fitted  with  2  or  3  heat  switch 
and  pilot  light.  When  the  first  set  of  cold  plates  is 
placed  in  warmer,  the  switch  is  turned  to  high  heat 
and  left  on  for  fifteen  (15)  minutes,  when  the 
lower  heat  is  turned  on  and  keeps  the  contents  hot. 

Dish  Washer. 

Art.  42:  Electric  dish  washers  are  of  many 
makes — occupy  small  space — do  their  work  quickly 
and  well  and  need  little  attention.  They  may  be 
fitted  with  a  switch  on  machine  or  at  wall.  (See 
Art.  16.) 

Metal  Polisher. 

Art.  43 :  An  electric  silver  and  metal  polisher 
consists  of  a  l/\  h.p.  or  l/2  h.p.  or  Irrger.  The  ends 
of  the  motor  shaft  are  arranged  to  receive  various 
brushes,  buffers,  felt  wheels  and  other  fittings,  all 
of  which  can  be  obtained  with  the  outfit.  By  using 
such  a  machine  the  knives,  forks,  spoons  and  silver- 
ware may  be  kept  in  the  best  condition  with  a  small 
expenditure  of  time  and  energy.  Should  have 

183 


switch  and  receptacle  on  wall,  omitting  pilot  light. 
(See  Art.  18.) 

Ice  Cream  Freezer. 

Art.  44:  An  electric  ice  cream  freezer  insures 
the  best  and  purest  home  product  with  but  little 
trouble.  TJie  electric  current  expense  is  negligible. 
Should  have  switch  on  machine  with  receptacle  on 
wall  or  combined  switch  and  receptacle  on  wall, 
omitting  pilot  light.  (See  Art.  18.) 

Electric  Cooking  Range 

Art.  45 :  Cooking  by  electricity  is  fast  coming 
into  more  general  use.  The  freedom  from  odors 
and  escaping  gas,  the  cleanliness  and  the  application 
of  heat  only  where  needed,  appeals  strongly  to  the 
housekeeper  and  in  many  parts  of  our  country,  such 
cooking  may  now  be  done  as  cheaply  as  with  gas. 
(See  Art.  5.) 

An  electric  range  for  a  family  of  six  would  oc- 
cupy a  floor  space  of  about  22  inches  by  28  inches. 
It  is  generally  fitted  with  a  number  of  separate 
switches  for  the  various  parts  and  utensils  and 
should  be  on  a  separate  3-wire  feeder  with  3-pole 
main  switch  and  pilot  light.  (See  Kitchen,  p.  170.) 

Ironing  Table. 

Art.  46:  Laundry  ironing  tables  may  be  pur- 
chased complete  with  swinging  arms  to  take  care  of 
the  cords  and  with  two  (2)  irons  for  different 
classes  of  work  and  so  arranged  with  automatic 
stands  that  the  iron  when  not  in  actual  use  takes 
only  enough  current  to  keep  it  hot.  (See  Art.  23.) 
Clothes  Washer  and  Wringer. 

Art.  47 :  The  simplest  type  of  electric  clothes 
washer  and  wringer  may  be  mounted  on  the  tubs 

184 


and  removed  when  not  in  use.  Other  types  have  all 
parts  mounted  on  one  stand  which  may  be  on  roll- 
ers to  bring  it  to  the  tubs  on  wash  days  and  remove 
it  at  other  times.  Such  a  machine  for  a  family  of 
six  would  occupy  a  floor  space  of  about  28  inches 
by  32  inches  and  the  washing  would  be  done  better 
than  by  hand  and  with  no  danger  of  tearing  laces 
and  lingerie.  Has  switch  on  the  machine  and  should 
connect  to  receptacle  on  wall.  (See  Laundry,  p. 
170.) 

Starch  Cooker. 

Art.  48 :  A  convenient  and  inexpensive  appliance 
in  the  house  laundry  is  an  electrically  heated  pot 
for  cooking  starch.  Should  be  connected  to  pilot 
switch  and  receptacle.  (See  Art.  18.) 

Sewing  Machine  Motor. 

Art.  49:  Every  home  should  have  the  sewing 
machine  fitted  with  a  motor  which  may  be  very 
small  in  size  and  can  be  arranged  to  start  and  stop 
by  pressing  a  contractor  with  the  foot.  It  is  very 
inexpensive  to  operate  and  saves  many  a  doctor's 
bill  where  much  sewing  is  done.  The  motor  may 
be  no  volts  and  should  be  connected  to  a  base 
receptacle. 

Bath  Room  Heater. 

Art.  50:  Heating  rooms  by  electricity  is  not  yet 
an  economic  fact,  but  for  special  cases  where  not  in 
continual  use,  they  are  very  convenient  and  not  too 
expensive  to  operate.  When  taking  a  bath  on  a 
winter  morning  when  the  hot  water  is  turned  on  an 
electric  heater  may  also  be  turned  on  and  by  the 
time  the  tub  is  ready,  the  chill  will  be  taken  out  of 
the  air.  For  this  purpose  the  heaters  should  have 

185 


a  capacity  of  four  watts  per  cubic  foot  of  room,  al- 
though this  is  much  greater  than  would  be  needed 
for  continuous  heating.  These  heaters  should  be 
on  separate  circuits  and  be  supplied  with  combina- 
tion pilot  switches  and  receptacles.  (See  Art.  18. ) 
(See  Math  Room,  p.  174.) 

Other  Bath  Room  Appliances. 

Art.  51:  Curling  iron  heaters  may  be  mounted 
on  the  surface  of  the  wall  and  are  very  small  in 
size  and  consume  current  only  when  the  iron  is  in- 
serted into  the  heater.  Hot  water  cups  or  stoves 
are  much  used,  take  up  little  space  and  should  be 
connected  to  a  combination  pilot  switch  and  recep- 
tacle. (See  Art.  18.) 

Entrance  Ball  Calls. 

Art.  52:  The  push  button  at  the  main  entrance 
door  should  not  ring  on  the  annunciators,  but  should 
be  a  distinctive  call,  ringing  a  separate  bell  in 
kitchen  or  pantry.  An  extension  bell  should  be 
placed  in  servant's  room  or  corridor  and  a  second 
extension  may  be  placed  in  a  sewing  room  that  is 
much  used.  These  extensions  are  controlled  by  small 
lever  switches  for  cutting  them  off  in  time  of  sick- 
ness. The  push  button  at  rear  entrance  should  ring 
a  buzzer  in  the  kitchen,  but  without  the  extensions. 

Bell  Annunciators. 

Art.  53  :  An  annunciator  should  be  placed  in  the 
kitchen  with  bell  different  in  sound  from  adjacent 
bells  and  fitted  with  an  indicating  drop  from  each 
of  the  rooms,  porches  and 'baths  in  the  house. 

A  second  annunciator  is  often  placed  in  servants' 
corridor  and  a  third  annunciator  may  be  placed  in 
the  sewing  room. 

186 


These  two  or  three  annunciators  ring  and  indicate 
simultaneously  for  each  call  and  are  connected  to- 
gether by  two  or  three  wires  more  than  the  total 
number  of  calls  or  drops  on  each. 

When  a  call  is  answered  from  any  annunciator,  a 
push  at  bottom  of  the  annunciator  resets  all  the 
annunciators,  thus  letting  others  know  that  the  call 
is  being  attended  to. 

Wall  Pushes. 

'  Art.  54:  \Yall  pushes  are  placed  in  the  door 
trims  of  the  various  rooms,  porches,  bath,  etc.,  and 
connected  to  the  nearest  annunciator.  Bath  room 
pushes  are  sometimes  placed  over  tub  rather  than 
at  the  door. 

Table  Pushes. 

Art.  55 :  In  some  rooms  such  as  the  living  room, 
it  is  often  desirable  to  have. a  table  push  on  a  flex- 
ible cord  connected  to  a  floor  receptacle.  These 
portable  pushes  are  usually  connected  to  the  same 
wires  as  the  wall  push  in  such  rooms.  In  case  of 
the  dining  room,  the  table  push  rings  a  separate 
buzzer  in  the  pantry. while  the  wall  push  rings  the 
annunciator. 

Bed  Pushes. 

Art.  56:  Portable  push  buttons  are  frequently 
located  at  beds  and  they  connect  to  the  same  wires 
as  the  wall  pushes.  (See  Art.  iQe.) 

When  the  mistress  of  the  house  has  a  special 
maid,  her  bed  portable  push  is  usually  connected  to 
a  buzzer  in  the  maid's  room. 

Battery  and  Cabinet. 

Art.  57:  The  bell  system  may  be  operated  from 
six  to  eight  cells  of  dry  battery,  placed  in  a  cabinet 

187 


which  may  be  located  in  the  cellar.  It  is  often 
well  to  use  these  batteries  in  duplicate  with  a  throw- 
over  switch  so  that  while  one  set  is  being  replaced 
or  renewed,  the  other  set  is  in  use.  (See  Cellar,  p. 
169.) 

Bell  Ringing  Transformer. 

Art.  58:  Where  alternating  current  is  used  for 
lighting,  the  bell  system  can  be  operated  by  a  small 
bell  ringing  transformer  which  may  be  placed  in 
the  cellar  and  connected  to  one  of  the  lighting  cir- 
cuits. These  transformers  may  also  be  used  for 
house  intercommunicating  telephone  ringing,  when 
the  telephones  are  on  metallic  circuit.  They  cannot 
be  used  for  telephone  talking,  which  requires  bat- 
tery or  direct  current.  (See  Cellar,  p.  169.) 

Public  Telephone. 

Art.  59:  It  is  quite  usual  to  put  conduits  in  a 
residence  for  use  of  the  Public  Telephone  Co.  and 
thus  keep  their  wires  out  of  sight.  A  Public  Tele- 
phone outlet  may  be  placed  in  the  kitchen  or  pantry 
with  extensions  to  living  room,  owner's  bedroom 
and  to  still  other  points  if  desired.  A  ^4-inch  con- 
duit is  ample  for  the  above  equipment. 

Standard  Wiring  Symbols. 
Art.  60 :  Owners,  architects  and  contractors 
would  save  much  time  and  misunderstanding  by 
familiarizing  themselves  with,  and  using,  the  stand- 
ard symbols  as  recommended  by  The  National  Elec- 
trical Contractors'  Association  and  The  American 
Institute  of  Architects,  when  indicating  on  plans 
just  what  is  desired  in  the  way  of  outlets,  fixtures, 
receptacles,  etc.,  etc.,  as  given  on  the  next  page. 

188 


STANDARD  SYMBOLS  FOR  WIRING  PLANS 

As  adopted   and   recommended   by  The   National   Electrical  Con- 

tractors Association  of  the  United  States  and  The  American 

Institute  of  Architects 

w     Ceiling    Outlet;    Electric    only.     Numeral    in    center    indicates    number    of 
Xl<  Standard  16  C.  P.  Incandescent  Lamps. 

fm<4  Ceiling  Outlet;    Combination.     %  indicates  4-16   C.   P.    Standard   Incandes- 
>4<5  cent  Lamps  and  2  Gas  Burners. 

Q     If  gas  only. 

|>5<     Bracket    Outlet;    Electric    only.     Numeral   in    center    indicates    number   of 
I>6<  Standard  16  C.   P.   Incandescent  Lamps. 

|>^<4  Bracket  Outlet;   Combination.     %  indicates  4-16  C.   P.   Standard  Incandes- 
I>*<2  cent  Lamps  and  2  Gas  Burners. 

IK     If  gas  only. 

Ij-,      Wall  or  Baseboard   Receptacle   Outlet.     Numeral  in  center  indicates  num- 

rt^J  her  of   Standard  16   C.   P.    Incandescent  Lamps. 

M     Floor   Outlet.     Numeral  in  center  indicates  number  of   Standard   16  C.   P. 
Incandescent  Lamps. 
¥~$Q  Outlet  for  Outdoor  Slandard  or  Pedestal;  Electric  only.     Numeral  indicates 

number  of  Standard  16  C.  P.  Lamps. 

XX  £  Outlet  for  Outdoor  Standard  or  Pedestal;   Combination.     %  indicates  6-16 
=*6.          C.  P.  Standard  Incandescent  Lamps;  6  Gas  Burners. 
£5J     Drop  Cord  Outlet. 

(^)     One  Light  Outlet,  for  Lamp  Receptacle. 
(J     Arc  Lamp  Outlet. 

fo      Special  Outlet,  for  Lighting,   Heating  and  Power  Current,  as  described  in 
Specifications. 

C2QO  Ceiling  Fan  Outlet. 


S1  S.  P.  Switch  Outlet. 

S'  D.  P.  Switch  Outlet. 

S3  3-Way  Switch  Outlet. 

S"  4-Way  Switch  Outlet. 

S"  Automatic  Door  Switch  Outlet 

S£  Electrolier  Switch  Outlet. 


Show  as  many  .  Symbols  as  there  are 
Switches.  Or  m  case  of  a  very 
large  group  of  Switches,  indicate 
number  of  Switches  by  a  Roman 
numeral,  thus:  S1  XII,  meaning  12 
Single  Pole  Switches. 

Describe  Type  of  Switch  in  Specifica- 
tions, that  is, 

Flush  or  Surface,  Push  Button  or 
Snap. 


Meter  Outlet. 

Distribution  Panel. 

Junction  or  Pull  Box. 

Motor  Outlet;   Numeral  in  center  indicates  Horse-Power. 

Motor  Control  Outlet. 

=y~y=  Transformer. 

— —  — —  Main  or  Feeder  run  concealed  under  Floor. 

— — — — —  Main  or  Feeder  run  concealed  under  Floor  above. 

—  —  —  —  —  —  Main  or  Feeder  run  exposed. 

Branch  Circuit  run  concealed  under  Floor. 

— — — —  Branch  Circuit  run  concealed  under  Floor  above. 
Branch  Circuit  run  exposed. 


189 


STANDARD   SYMBOLS    (Continued) 
— • — ^ —    Pole  Line. 
•  Riser. 

W  Telephone  Outlet;   Private  Service. 

M  Telephone  Outlet;   Public  Service. 

Q  Bell  Outlet. 

D/  Buzzer  Outlet. 

02  Push  Button  Outlet;   Numeral  indicates  number  of  Pushes. 

— <|>  Annunciator;   Numeral  indicates  number  of  Points. 

-^  Speaking  Tube. 

-©  Watchman  Clock  Outlet. 

— I  Watchman  Station  Outlet. 

Hg»  Master  Time  Clock  Outlet. 

— D  Secondary  Time  Clock  Outlet. 

[J]  Door  Opener. 

12]  Special  Outlet,  for  Signal  Systems,  as  described  in  Specifications. 

l|||l|      Battery  Outlet. 

(  Circuit  for  Clock,  Telephone,  Bell  or  other  Service,  run  under  Floor, 

J         concealed. 

(  Kind  of  Service  wanted  ascertained  by  Symbol  to  which  line  connects. 

(Circuit  for  Clock,   Telephone,   Bell  or  other   Service,   run  under   Floor 

•<          above,   concealed. 

(  Kind  of  Service  wanted  ascertained  by  Symbol  to  which  line  connects. 

NOTE — If  other  than   Standard  16  C.   P.   Incandescent  lamps  are  de- 
sired.  Specifications  should  describe  capacity  of  Lamp  to  be  used. 


When  in  Doubt. 

Art.  6 1 :  Be  guided  by  the  sections  on  " Approved 
Apparatus  and  Supplies"  (page  135),  and  by  "Elec- 
trical Inspection"  (page  140). 


190 


Resuscitation  From  Electric  Shock. 

As  recommended  by  The  National  Electric  Light 
Association.  Follow  these  instructions  even  if  vic- 
tim appears  dead. 

I.     Immediately  Break  the  Circuit. 

With  a  single  quick  motion,  free  the  victim  from 


FIG.  i— INSPIRATION; 
PRESSURE    OFF. 


the  current.  Use  any  dry  non-conductor  (clothing, 
rope,  board)  to  move  either  the  victim  or  the  wire. 
Beware  of  using  metal  or  any  moist  material.  While 
freeing  the  victim  from  the  live  conductor  have 
every  effort  also  made  to  shut  off  the  current 
quickly. 

101 


II.     Instantly  Attend  to  the  Victim's  Breathing. 

As  soon  as  the  victim  is  clear  of  the  conductor, 
rapidly  feel  with  your  finger  in  his  mouth  and 
throat  and  remove  any  foreign  body  (tobacco,  false 
teeth,  etc.).  Then  begin  artificial  respiration  at 
once.  Do  not  stop  to  loosen  the  victim's  clothing 
now ;  every  moment  of  delay  is  serious.  Proceed 
as  follows : 

(a)  Lay  the  subject  on  his  belly,  with  arms  ex- 
tended as  straight  forward  as  possible  and  with  face 
to  one  side,  so  that  nose  and  mouth  are  free  for 
breathing  (see  Fig.  i).    Let  an  assistant  draw  for- 
ward the  subject's  tongue. 

(b)  Kneel  straddling  the  subject's  thighs,  and 
facing  his  head;  rest  the  palms  of  your  hands  on 
the  loins  (on  the  muscles  of  the  small  of  the  back), 
with  fingers  spread  over  the  lowest  ribs,  as  in  Fig.  i . 

(c)  With   arms  held   straight,   swing   forward 
slowly  so  that  the  weight  of  your  body  is  gradually, 
but  not  violently,  brought  to  bear  upon  the  subject 
(see  Fig.  2).     This  act  should  take  from  two  to 
three  seconds. 

(d)  Then  immediately  swing  backward  so  as  to 
remove  the  pressure,  thus  returnig  to  the  position 
shown  in  Fig.  i. 

(e)  Repeat  deliberately  twelve  to  fifteen  times  a 
minute  the  swinging  forward  and  back — a  complete 
respiration  in  four  or  five  seconds. 

(f )  As  soon  as  this  artificial  respiration  has  been 
started,  and  while  it  is  being  continued,  an  assistant 
should  loosen  any  tight  clothing  about  the  subject's 
neck,  chest,  or  waist. 

192 


2.  Continue  the  artificial  respiration  (if  neces- 
sary, two  hours  or  longer),  without  interruption, 
until  natural  breathing  is  restored,  or  until  a  physi- 
cian arrives.  If  natural  breathing  stops  after  being 
restored,  use  artificial  respiration  again. 

c.  Do  not  give  any  liquid  by  mouth  until  the  sub- 
ject is  fully  conscious. 

4.  Give  the  subject  fresh  air,  but  keep  him  warm. 
III.  Send  for  Nearest  Doctor  as  Soon  as  Acci- 
dent is  Discovered. 


Switchboard  and  Electrical  Fires 

A  liquid  extinguisher,  called  Pyrene,  has  recently 
been  put  on  the  market.  Experiment 'and  accept- 
ance tests  made  by  the  largest  electric  light,  power, 
railroad  and  transit  companies  in  America  and  by 
the  underwriters  laboratories,  indicate  that  it  is  of 
great  value  to  the  electrical  industry.  At  several 
of  the  tests  made  short-circuit  electrical  arcs  larger 
than  any  that  have  ever  before  been  intentionally 
produced,  were  successfully  handled  by  this  extin- 
guisher, arcs  of  an  indicated  energy  of  4OO-h.p. 
being  snuffed  out  by  a  few  ounces  of  the  liquid. 
It  was  also  found  difficult  to  re-establish  the  arcs 
when  put  out  by  this  preparation. 

The  extinguisher  is  small  and  light,  working  on 
the  principle  of  a  double-acting  syringe,  can  be 
conveniently  located  and  is  easily  carried.  As  the 
liquid  will  not  freeze  at  60°  below  zero  it  can  be 
left  in  exposed  places  during  the  winter.  No  peri- 
odic recharging  is  required,  although  they  are  re- 
fillable  after  use. 

193 


MISCELLANEOUS. 

DEFINITIONS  OF  ELECTRICAL   UNITS. 

All  electrical  units  are  derived  from  the  follow- 
ing mechanical  units: 

The  Centimeter  is  the  unit  of  length,  and  equals 
•3937  inch,  or  .000000001  of  a  quadrant  of  the 
earth. 

The  Gram  is  the  unit  of  mass,  and  is  equal  to 
1 5-432  grains,  the  mass  of  a  cubic  centimeter  of 
water  at  4°  C. 

Tht  Second  is  the  unit  of  time  and  is  the  time 
of  one  swing  of  a  pendulum,  swinging  86464.09 
times  per  day,  or  the  i/864OOth  part  of  a  mean 
solar  day. 

The  Volt  is  the  unit  of  electro-motive  force  [E]. 

Electromotive  force,  which  is  the  force  that 
moves  electricity,  is  usually  written  E.  M.  F.  (in 
formulae  E)*and  various  writers  use  it  to  express 
potential,  difference  of  potential,  electric  pressure 
and  electric  force. 

One  volt  will  force  an  ampere  of  current  through 
one  ohm  of  resistance.  Its  value  is  purely  arbi- 
trary, but  fixed. 

The  Ohm  is  the  unit  of  resistance  [R]  and  it  is 
equal  to  the  resistance  of  a  column  of  pure  mer- 
cury i  square  millimeter  in  section  and  106.3  centi- 
meters long  at  the  temperature  of  melting  ice. 

One  ohm  is  that  resistance  through  which  one 
ampere  of  current  will  flow  at  a  pressure  of  one 
volt  of  E.  M.  F. 

The  Megohm  —  1,000,000  ohms. 

The  Ampere  is  the  unit  of  current  strength  [C]. 
Its  value  may  ,be  defined  as  that  quantity  of  elec- 


tricity  which  flows  through  one  ohm  of  resistance 
when  impelled  by  one  volt  of  E.  M.  F. 

One  ampere  of  current  flowing  through  a  bath 
will  deposit  0.017253  grain  of  silver  or  0.004085 
grain  of  copper  per  second . 

The  Coulomb  is  the  unit  of  quantity  [Q],  and  is 
the  quantity  of  electricity  passing  per  second,  when 
the  current  is  one  ampere. 

The  Farad  is  the  unit  of  capacity  [K],  and  is 
capacity  that  will  contain  one  coulomb  at  a  poten- 
tial of  one  volt. 

A  condenser  of  one  farad  capacity,  if  charged  to 
two  volts,  will  contain  two  coulombs ;  if  to  100 
volts,  100  coulombs,  etc. 

The  Microfarad  [mfd]  -  -  one  millionth  of  a 
farad. 

The  Joule  is  the  unit  of  work  |_\V].  It  is  the 
work  done  or  heat  generated,  by  a  watt  in  a  sec- 
ond. It  is  equal  to  .7373  foot-pound. 

The  Watt  is  the  unit  of  electrical  power  [P], 
is  the  energy  contained  in  a  current  of  one  ampere 
with  an  electromotive  force  of  one  volt.  746  watts 

=  one  horsepower.  A  current  of  7.46  amperes  at 
100  volts  will  do  the  work  of  the  one  horsepower. 

A  Horse-Power  in  a  steam  engine  or  other 
mover  is  550  Ibs.  raised  one  foot  per  second,  or 
33,000  Ibs.  one  foot  per  minute. 

The    Kilowatt   [kw]  equals  to  1,000  watts. 

The  E.  M.  F.  is  distributed  according  to  the  re- 
sistance of  the  various  parts  of  the  circuit,  except 
where  there  is  counter  E.  M.  F. 

Counter  E.  M.  F.  is  like  back  pressure  in  hy- 
draulics. Thus,  to  find  the  available  E.  M.  F.,  or 

195 


the  resulting  current  against  a  resistance  where 
there  is  a  counter  E.  M.  F.,  the  counter  E.  M.  F. 
must  be  deducted.  For  example:  Suppose  a  stor- 
age battery  with  a  resistance  of  .02  ohm  and  a 
C.  E.  M.  F.  of  15  volts,  and  you  wish  to  charge  it 
with  a  dynamo  which  gives  an  E.  M.  F.  of  20  volts 
at  the  battery  binding  posts.  There  are  20  —  15  - 
5  volts  working  through  a  resistance  of  .02  of  an 
ohm  with  consequently  a  current  of  250  amperes. 
The  impressed  voltage  is,  however,  20  volts,  and 
not  5  volts,  and  the  power  is  20  X  250  =  5000 
watts,  and  not  5  X  250  =  1250  watts,  as  might  per- 
haps be  supposed.  It  is  obvious  that  the  C.  E. 
M.  F.  has  acted  as  a  true  resistance.  In  the  above 
case  5  ;X  250  —  1250  watts  were  wasted  in  over- 
coming the  resistance  of  the  storage  battery  and  the 
remaining  3750  watts  were  stored  up  in  the  chem- 
ical changes  which  they  brought  about  in  the  active 
material  of  the  storage  battery. 

Mils  =  Thousandths  of  an  inch. 

d2  —  circular  mils. 

The  Circular  Mil  is  now  generally  used  as  the 
unit  of  area  when  considering  the  cross-section  of 
electric  conductors,  the  resistance  being  inversely, 
and  weight  of  copper  directly,  proportion  to  the 
circular  mils. 

General  Formulae    Ohms  Laws    (Direct  Current.) 
C.  =  current  in  amperes. 
E.  ~  electromotive  force  in  volts. 
R  =  resistance  in  ohms. 
W.  =  energy  in  watts. 

E.  E. 

C  =  -  E.  —  C.R.  R.  —  - 

R.  C. 


E2 
C.  E.  ==  W.  VV.  =  -  C8  R.  =  W. 

R 
W. 

-  =  H.P.  W.  =746X  H.P. 

746   ' 

Formulae  giving  the  volts  or  amperes  necessary 
for  a  given  horsepower  on  circuits  of  constant  cur- 
rent, and  constant  potential,  respectively: 
746  X  H.P. 

ir»     __ 

C.  X  K. 
.      746  X  H.P. 


E.  X  K. 

E.  =  potential  of  circuit. 
C.  =  afnperes. 
K.  =  efficiency  of  machine. 
H.P.  =  horsepower. 

General   Formulae   for   Direct  Current  Light  and 
Power  Wiring.      When  possible  use  the  tables  on 

pages  52  and  69,  for  conveniences. 
c.m.  =  circular  mils.     (See  page  81). 

d.  —  length  of  wire,  in  feet,  on  one  side  of  circuit. 
n.  =  number  of  lamps  in  multiple. 
c.  =  current  in   amperes  per  lamp  (see  p.  115). 
v.  —  volts  lost  in  lines  (see  pp.  32  and  70). 
r.  —  resistance  per  foot  of  wire  to  be  used. 
10.8  ohms  —  resistance  of  one  foot  of  commercial 
copper  wire  having  a  diameter  of 
one  mil  and  a  temperature  of  75° 
Fahrenheit. 
ivr 


It  is  an   easy  matter  to  find   any  of  the  above 
values  by  the  following  formulae  for  direct  current: 

10.8  X2d.  X  n-  X  c. 
c.m.  = 

v. 

10.8  X  2d.  X  n.  X  c.  c.m.  X  v. 


c.m.  10.8  X  2d.  X  n. 

c.m.  X  v.                                      c.m.  X  v. 
2d.  = 


10.8  X  2d."X  c.  10.8  X  c.  X  n. 

v. 

»-       

n.  X  c.  X  2d. 

v. 
v.    =  n.  X  c.  X  2d.  X  r. 


2d.  X  n.  X  r. 

v.  v. 

c.  X  2d.  X  r.    .  n.  X  c.  X  r. 

To  find  the  efficiency  of  incandescent  lamps  when  : 
C.  —  current  in  amperes. 
E.  =  electromotive  force  in  volts. 

E 
R.  —  —  =  resistance  of  lamp,  hot. 

C 

C.P.  —  candlepower  of  lamp. 
W.  c.p.  =  watts  per  candlepower   (a  measure  of 

efficiency  of  lamp).     (See  p.  115.) 
One  electrical  H.P.  —  746  watts. 

198 


C.XE. 

Watts  per  C.P.  = 

C.P. 

746 

Number  candles  per  electric  H.P.  = 

W.c.p, 

As  the  efficiency  of  conversion  of  good  dynamos 
is  90  per  cent.,  the  calculations  of  candles  per  elec- 
trical H.P.  must  be  multiplied  by  this  factor  to  give 
the  number  of  candles  per  mechanical  horse-power. 

The  weight  and  resistance  per  mile  of  round  wire, 
where  d.  is  the  diameter  in  mils,  are : 

Weight.          Resistance  at  75^ 

d2  380066 

For  copper  wire Ibs.     ohms. 

62.5  d2 

d2  56970 

For  iron  wire Ibs. ohms 

72  d2 

To  ascertain  the  sectional  area : 
Diameter  =  d. 
Sectional  area  in  circular  mils  —  d2. 

Copper  wire  is  1.14  times  the  weight  of  an  iron 
wire  of  the  same  size. 

A  copper  wire  334  circular  mils  in  cross-section 
and  1000  feet  in  length  weighs  one  pound. 

The  percentage  of  conductivity  of  any  wire  is 
found  by  multiplying  the  resistance  of  a  pure  wire 
of  the  same  length  and  weight  at  the  same  tem- 
perature by  100,  and  dividing  the  product  by  th<: 
resistance  of  the  wire  as  measured. 

199 


Lull.          Equivalent    Value   in    Other    Unit*. 


1    H.    P.=s< 


746  watts. 

.846  K.  W. 

33,000  ft.-lbs.  per  minute. 
550  ft.-lbs.   per  second. 
2,545  heat-units  per  hour. 
42.4  heat-units  per  minute. 
.707  heat-unit  per  second. 
.175   Ib.   carbon   oxidized   per   hr. 
2.64    Ibs.     water    evaporated    per 
hour  from  and  at  212°  F. 


1   H.   P. 

Hour 


746   K.   W.   hours. 
1,980,000  ft.-lbs. 

2,545  heat-units. 
273,740  k.   g.   m. 

.175     Ib.     carbon     oxidized    with 

perfect  efficiency. 
2.64    Ibs.    water    evaporated    from 

and  at  212°   F. 

17.00    Ibs.    water    raised    from    62° 
to  212"  F. 


1    KUo- 
watt 


1   Watt 
per   sq.   = 
m. 


4 


1,000  watts. 

1.34  H.  P. 

2,654,200  ft.-lbs.  per  hour. 
44,240  ft.-lbs.  per  minute. 

737.3  ft.-lbs.  per  second. 
3,412  heat-units  per  hour. 
56.9  heat-units  per  minute 
.948  heat-unit  per  second. 
.2275    Ib.     carbon     oxidized 

hour. 

3.53    Ibs.     water    evaporated 
hour  from  and  at  212°  F. 


per 
per 


8.19  _heat    units    per    sq.    ft.    per 

minute. 

6,371  ft.-lbs.  per  sq.  ft.  per  minute 
.193  H.  P.  per  sq.  ft. 


1  Kilo- 
gram       = 
Metre 


7.233.  ft.-lbs. 
.00000365   H.   P.  hour 
.00000272  K.   W.  hour. 
.0093   heat-units. 


1   Ib.   Wat- 
er    Evapo- 
rated      =. 
from    and 
at  212°   F. 


.     .283  K.  W.  hour. 
.379  H.    P.   hour. 
965.7  heat-units. 
103,900  k.  g.   m. 
1,019,000  joules. 
751,300  ft.-lbs. 

.0664  Ib.   of  carbon  oxidized. 


200 


Unit. 


Equivalent   Value   in   Other   Units. 


1   Heat- 
unit 


I   Heat        f 
unit   per 
sq.    it.     =1 
per   mm. 


1,055  watt  seconds. 
778  ft.-lbs. 
107.6 

.000293  K.  W.  hour. 
.000393  H.   P.  hour. 
.0000688  Ib.  carbon  oxidized. 
.001036     Ibs.     water     evaporated 
from  and  at  212°  F. 


.122  watts  per  sq.  in. 
.0176  K.  W.  per  sq.   ft. 
.0236   H.   P.   per  sq.   ft. 


1  joule  per  second. 

.00134  H.  P. 

3,412  heat-units  per  hour. 
.7373  ft.-lb. 
.0035    Ib    water    evaporated    per 

hour. 
44.24   ft.-lbs.   per  minute. 


1  K.  W. 

Hour       = 


1,000  watt  hours. 

1.34   H.   P.  hours. 
2,654,200  ft.-lbs. 
3,600,000  joules. 

3,412  heat-units. 
367,000  kilogram  metres. 

,235     Ib.    carbon     oxidized    with 

perfect  efficiency. 
3.53    Ibs    water    evaporated    from 

and  at  212°    F. 

11.75  Ibs.  of  water  raised  from  62° 
to  212°  F. 


1   Joule  =- 


1  watt  second. 

.000000278  K.  W.  hour. 

.102  k.  g.  m. 
.0009477  heat-units. 
.7373  ft.-lb. 


1  ft.-lb.   =• 


1.356   joules. 
.1383  k.  g.  m. 
.000000377  K.  W.  hours. 
.001285  heat-units. 
0000005  H.  P.  hour. 


1  Ib.  Car- 
bon Oxi- 
dized ^ 
with  Per-  * 
feet  Ef- 
ficiency. 


14,544  heat  units. 

1.11  Ib.  anthracite  coal  ox. 
2.5  Ibs.  dry  wood  oxidized. 
21  cu.   ft.   illuminating  gas. 
4.26   K.  W.  hours. 
5.71  H.  P.  hours. 
11,315;000  ft.-lbs. 

15    Ibs.    of   water    evaporated    from 
and  at  212°   F. 


201 


CONDUIT    SIZES    FOR    DIFFERENT    SIZE    WIRES. 

Size  of  Pipe 


No. 
B&S 

Circular 
Mills. 

Amperes 
Rubber. 

1 

Wire. 

2 
Wire. 

0 

Wire. 

18 

1,624 

3 

54 

54 

54 

16 

2,583 

6 

X 

54 

54 

14 

4,107 

15 

54 

54 

34 

12 

6,530 

20 

54 

34 

34 

10 

10,380 

25 

54 

34 

l 

8 

16,510 

35. 

54 

l 

1 

6 

26,250 

50. 

34 

l 

154 

5 

33,100 

55 

34 

154 

154 

4 

41,740 

70. 

34 

154 

154 

3 

52,630 

80. 

34 

154 

154 

2 

66,370 

90 

34 

154 

2 

1 

83,690 

100 

l 

154 

2 

0 

105,500 

125 

l 

2 

2 

2.0 

133.100 

150 

l 

2 

2 

3.0 

167,800 

175 

154 

2 

254 

4.0 

211,600 

225 

154 

2 

254 

200,000 

200 

154 

2 

254 

250,000 

235 

154 

254 

254 

300.000 

275 

154 

254 

3 

350,000 

300 

154 

'  254' 

3 

400,000 

325 

154 

3 

3 

450,000 

380 

2 

3 

354 

500.000 

400 

2 

3 

354 

In  laying  out  a  conduit  job,  first  ascertain  the  size  and  number 
of  wires  required,  then  take  the  sizes  of  conduit  from  the  above 
table.  One-half  inch  is  usually  used  for  branch  conduits  and  is 
the  smallest  size  permitted  by  the  National  Electrical  Code.  In 
running  several  conduits  together,  a  pull  *box  will  be  found  more 
economical  than  elbows  for  making  turns,  as  one  pull  box  will  take 
the  place  of  several  elbows. 


CONDUIT  AND   WIRE  DIAGRAM 

SHOWING  ACTUAL  RELATION  OP  VARIOUS  SIZES  DOUBLE  BRAID  RUBBER 
COVERED  WIRE  TO  CONDUIT. 


203 


Underground  Conduit:  The  use  of  bitumin- 
ized  fibre  conduit  for  all  underground  work  is  rec- 
ommended on  account  of  its  simplicity  and  ease  in 
installing.  It  is  light  in  weight  and  practically 
water  and  gas  proof  and  has  high  insulating  quali- 
ties. Unlike  metal  conduit,  for  underground  work, 
it  is  not  affected  by  electrolytic  action  and  may  be 
purchased  for  one-third  the  cost  of  iron  pipe. 
Bituminized  conduit  is  furnished  in  convenient 
lengths,  bends,  elbows,  tees  and  junction  boxes  in 
all  sizes  from  one  to  four  inches  as  per  table  given 
below.  It  may  be  laid  in  trenches  with  or  without 
concrete  and  is  especially  adapted  to  running  wires 
from  street  mains,  to  private  residences. 


UNDERGROUND  FIBRE  CONDUIT. 


INSIDE 

THICKNESS 

BENDS 

DIAMETER 

OF    WALL 

LENGTH 

RADIUS 

I 

inches 

i/4 

inch 

5 

feet 

8 

inches 

iX 

inches 

5/T6 

inch 

5 

feet 

10 

inches 

2 

inches 

3/8 

inch 

7 

feet 

12 

inches 

2l/l 

inches 

3/8 

inch 

7 

feet 

H 

inches 

3 

inches 

3/8 

inch 

7 

feet 

18 

inches 

3T4 

inches 

3/8 

inch 

7 

feet 

20 

inches 

3^2 

inches 

3/8 

inch 

7 

feet 

24 

inches 

4 

inches 

3/8 

inch 

7 

feet 

30 

inches 

204 

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BREAKING    WEIGHTS. 

ENGLISH    SYSTEM. 


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c 

Breaking 

Breaking 

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Vji 

Weight 

Weight 

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Hard  Drawn 

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8310 

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000 

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6580 

9140 

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364.8 

5226 

7400 

o 

324.9 

4558 

6300 

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2 

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4180 

3 

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2480 

3300 

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1967 

2700 

5 

l8l.9 

1559 

2080 

6 

l62 

1237 

1680 

7 

144-3 

980 

1350 

8 

128.5 

778 

1075 

9 

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6l7 

850 

10 

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489 

68  q 

ii 

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388 

545 

12 

80.81 

307 

420 

13 

71.96 

245 

340 

14 

64.08 

270 

15 

57.07 

153 

220 

16 

50.82 

133 

180 

17 

45.26 

97 

135 

18 

40.30 

77 

107 

ELASTIC  LIMIT. 

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Wire. 

£  W 

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Length  of  Belting  for  Various  Purposes. 


IT 


( 
\ 


Open  belting:  L  =  -  -  S.  -f  2C. 

2  \  8 

L  —  Length  of  belt. 

S  •=  Sum  of  pulley  diameters. 

C  =  Distance  between  centers  of  pulleys. 

D  =  Difference  of  pulley  diameters. 

TT  =3.141592,  or,  for  practical  purposes,  3.1416. 

For  calculating  the  length  of  belting  approxi- 
mately, add  one-half  the  circumference  of  each  pul- 
ley to  twice  the  distance  between  centers  of  the 
pulleys. 

To  find  the  horsepower  strength  of  double 
leather  belting  when: 

d.  '==  diameter  of  small  pulley  in  inches. 

r.  =  revolutions  of  small  pulley  per  minute. 

b.  •=  breadth  of  belting  in  inches. 
H.P.  =  horsepower  to  be  transmitted. 


H.P.  = 


1925 

"Double"  belting  is  expected  to  transmit  twice 
that  of  "single"  belting,  and  "light  double"  one  and 
one-half  times  that  of  "single." 

Strength  of  wrought  iron  or  steel  Shafting. 
(Formula  as  used  by  Pencoyd  Iron  Works.) 


sh         ^  R   p  = 


50 


or  d  =  V   7°R  '  P'  for  shafts  carrying  pulleys,  etc., 


m 


Rd' 

or  H.P.  = 

70 

s     * 

i  =  *y    720  d2  for  bare  shafts,  or  d  =  V    J — 

720 

3        

or  i  =  V  140  d2  for  shafts  carrying  pulleys,  etc.. 

2         

or  d  =  V  _il 
140 

H.P.  =  horse-power  transmitted, 
d  =  diameter  shaft  in  inches. 
R  =  revolutions  per  minute. 

1  =  length  between  supports  in  feet. 
To  find  the  horse-power  of  engines: 
in  which : 

H.P.  =  indicated  horse-power. 

Ps  =  travel  of  piston  in  feet  per  minute. 
A  ==  area  of  piston  in  square  inches. 
M.  E.  P.  =  mean  effective  pressure  in  pounds  per 

square  inch. 
Ip  =r  initial  pressure, 
and: 

34Xlp 

(a)  M.  E.  P.  = at  VA,  cut  off. 

•-57 

ii  Xlp 

(b)  M.  E.  P.  = at  y2  cut  off. 

13 

An  application  of  these  formulae  in  an  appropri- 
ate example  may  be  considered  in  the  following 
problem : 

213 


It  is  desired  to  determine  the  I.  H.  P.  of  an  en- 
gine whose  cylinder  is  10  inches  in  diameter  and 
whose  stroke  is  12  inches,  operating  at  300  revolu- 
tions per  minute,  the  initial  steam  pressure  being 
100  pounds  per  square  inch,  cutting  off  at  'J/2  and 
l/2  stroke,  respectively: 

34  X  Ip       34  X  ioo 
(a)  M.E.P.  =-  -  =  59-65  at  V4 

57  .  57 

cut  off. 

ii  X  Ip       34  X  ioo 
(&)  M.E.P.  =  =  84.6  at  }/2 

13  13 

cut  off. 
n 
A  =  —  X  diameter2  =  .7854  X  io2  =  78.54  square 

4 
inches. 

Ps  =  .2  feet  per  revolution  and  30  resolutions 
per  minute  =  600  feet  per  minute. 

Ps  X  A  X  M.  E.  P. 
I.  H.  P.  at  54. cut  off  =  - 

33,000 

600  x  78.54  x  59-65 

-  =  85.18 
33,000 

Ps  X  A  X  M.  E.  P. 
I.  H.  P.  at  */>  cut  off  =  - 

33,000 
600  X  78-54  X  84.6 


33,000 

214 


To  find  the  horse-power  of  a  pulley: 

Multiply  the  circumference  of  the  pulley  in  feet 
by  the  revolutions  per  minute,  and  the  product  thus 
obtained  by  the  width  of  the  belt  in  inches,  and  di- 
vide the  result  by  600. 

This  rule  is  founded  on  the  fact  that  good,  ordi- 
nary, single  leather  belting,  with  a  tension  of  fifty- 
five  pounds  per  inch  width,  will  require  fifty  square 
feet  of  belt  surface  passing  over  the  pulley  per  min- 
ute for  one  horsepower.  Fifty  square  feet  per 
minute  is  equal  to  a  belt  one  inch  wide  running  600 
feet  per  minute. 

To  find  the  speed  of  a  belt,  multiply  the  circum- 
ference of  the  driving  pulley  in  feet  by  the  revolu- 
tions per  minute. 

Belts  should  always  be  run  with  the  grain  side 
next  to  the  pulley. 

Rule  for  finding  size  of  dynamo  driving  pulleys. 

DXS 


Sl 

d  —  required  diameter  of  dynamo  pulley. 
D  =  diameter  of  engine  pulley. 
S  =  number  of  engine  revolutions  per  minute. 
S1  =  required  revolutions  of  armature  per  min- 
ute. 

The  light  cut-off  by  arc  lamp  globes  is 

Ordinary  glass  ........................  10% 

Light  ground  glass  ....................  30% 

Heavy   ground   glass  ..................  45  to  50% 

Strong  opal  glass  .....................  50  to  60% 

215 


INDEX  TO  CONTENTS. 


Appliances,    Current    Consuming,    Sugges- 
tions     % 181-186 

Approval,  of  Apparatus  and  Supplies 135 

Approved    Apparatus    and    Supplies 135 

Arc  Lamps,   Installation 130 

Arc  Lamps,   Series 86 

Arc  Lamps,  Series  Wiring 85 

Arc  Lamps,  Wiring,  High  Potential   (Con- 
stant Current) 131 

Arc  Lamps,  Wiring,   Low   Potential    (Con- 
stant Potential)    132 

Arms,   Guard    40 

Arresters,   Lightning,   Outside 48 

Arresters,   Lightning,   Station . . .  .  v n 

Attendance,  in  Generator  Room 22 

Auto-Starters    25 

Batteries,   Storage,  Installation  of 13 

Bearings,  Care  of 21 

Belts,  For  Generators  and  Motors 15 

Brushes,  Copper  and  Carbon 15-1? 

Bus-Bars    7 

Cabinets,   General   Specifications.  . 128-130 

Cabinets,  Wood  and  Metal 129 

Cables,  Armored,  Installation 157 

Cables,  Armored,  Makers  of 101 

Circuit  Breakers,   For  Generators 5 

Circuit  Breakers,   For   Motors 28 

Circuit   Breakers,    Installation 104-106 

Circuit  Breakers,  Where  Required 84 

Circuits,    Branch    I55~i56 

216 


Coils,  Economy    132 

Commutators,   Care  of 20 

Conduit,  Bushings    94 

Conduit  Fitting,  Use  of 160 

Conduit,  Fittings .  95 

Conduit,  Flexible  Steel,   Installation 158 

Conduits,  For  Bell  Wiring 159 

Conduit,  Metal,  Flexible  Steel 93 

Conduit,  Metal,   Rigid 92 

Conduit,   Non-Metallic   Flexible 92 

Conduits,   Rigid,   Metal,   Installation 158 

Conduit,  Underground,  Fibre 204 

Conduit,  Wiring   91 

Connectors,  Solderless  for  Wires  and  Cables  40 

Covers,  For  Motors  and  Generators 6 

Cross  Arms    59 

Current   Supply    146-149 

Cut-Outs,  Automatic    103 

Cut-Outs,   Link  Fuse 1 19-122 

Cut-Outs,  Protection  and  Care  of 85 

Extinguishers,  For  Electrical  Fires 12,  193 

Fires,   Electrical,   Extinguishing  of 193 

Fixtures,    Lighting,    Installation 98 

Fixtures,   Wiring  of 99 

Flexible  Tubing,  Installation  of  ("Knob" and 

Tube  Work")    83 

Formulae,  See  Index  on  Page 222 

Fuse    Blocks,    Specifications 121 

Fuses,  Enclosed,  Approved  Makes 124 

Fuses,    Enclosed,    Dimensions 125-126 

Fuses,  Enclosed,  Cartridge  and  Plug  Types  122-126 

Fuses,  For  D.  C.  Motors 30 

217 


Fuses,   Link,    Specifications 128 

Fuses,   Open   Link,   Dimensions 122,  127 

Fuses,  Refillable   (Unapproved) 124 

Generators,   Accessibility    5 

Generators,   Care  of 14 

Generators,    Directions    for   Starting 17-20 

Generators,    Foundations    4 

Generators,    Installation    . 3 

Generators  and  Motors,  Wiring  Diagrams .  .   33-38 

Ground,  Connections    46-51 

Ground   Detectors    13, 50 

Ground  Plates,   Installation  of 50 

Ground  Wires    12 

Grounding 151-152 

Grounding,  A.  C.  Secondary 46 

Grounding,  Generator  and  Motor  Frames .  .     4,  22 

Grounding,  Low  Potential  Circuits 45 

Grounding,   3~Wire  D.   C 45 

Guard  Irons,  Where  Required 60 

Hanger  Boards  133 

Heaters,  Electric,  Installation ,  .  .        133 

High  Voltage  Circuits   (5000) 55 

House  Wiring,  Suggestions 141-190 

Illumination,  By  Incandescent  Lamps 117-118 

Inspection,  Of  Wiring  Installations .        140 

Insulation   Resistance,   Testing 13 

Insulators,  Canopy,   For  Fixtures 107 

Insulators,    Petticoat    40-41 

Insulators,  Porcelain  Knobs  and  Cleats....         68 

Insulators,  Tree   41 

Joints,   Insulating    106-107 

"Knob  and  Tube"  Work 91-156 

218 


Lamps,  Arc  (See  Arc  Lamps)  .  . 216 

Lamps,   Incandescent,   Arrangement... 118 

Lamps,    Incandescent,   Data 114-117 

Lamps,  Mercury  Vapor 1 17 

1  .amp  Wiring,   Series  Incandescent 87 

Lighting,  Arc  and  Incandescent  Lamps....        119 
Lighting,     Suggestions     for    Architect     and 

(  hvner .  .  177-181 

Mains,  For  House  Wiring 152 

Motors,  Current  Required   (D.  C.) 3O-31 

Motors,  Efficiency  of  (D.  C.) 29 

Motors,   Installation   Diagrams 33~38 

Motors,   Installation   of 22-38 

Motors  and  Generators,  Wiring  Diagrams..   33-38 
Motors,  Starting  and  Stopping  Directions..          27 

Motors,  Wiring  Formula   for  D.  C 29 

Moulding,  Metal    159 

Moulding,  Metal,  Installation 90 

Moulding,  Metal,   Specifications    89 

Moulding,  Wood,  Installation   .  .  .  > 88 

Moulding,  Wood,  Specifications   88 

Moulding,  Wood,  Where  Used 159 

Xame  Plates,  for  Generators  and  Motors ....  6 
National  Electric  Light  Association,  Sugges- 
tions  from    141-193 

Ohm's  Law,  General  Formulae  (D.  C.) .  . .  .  196-197 

Outlets,  Location  of,  Diagrams   166-175 

Panels,  Distributing 153-155 

Poles,'  Directions  for  Setting 58 

Poles,  For  Light  and  Power  Wires 57-64 

Poles,  Per  Mile    62-63 

Poles,  Size  and  Weight 61 

219 


Rates,  Current  Costs   150 

Receptacles,  Flush,  Distribution. 168 

Resistance,  Insulation  of  Wiring 107-108 

Resistance,  Measurement  (Megger  Method)         51 

Rheostats  or  Controllers 9,  24 

Roof  Structures 39,  43 

Rosettes,   Wiring   of 99 

Service   Blocks    42 

Service   Heads 44 

Service,  How  to  Obtain 141-143 

Shock,  Electric,  Resuscitation  from 191-193 

Society  for  Electrical  Development,  Sugges- 
tions  from    186-190 

Sockets,  Lamp,  Construction  of 102 

Sockets,  Lamp,  Special 102 

Splicing  Devices,  Approved 40 

Splicing,  Wires  and  Cables 40 

Switchboards,  Location  of  8 

Switches,  Closet    .  166-167 

Switches,  Cut-outs,  Circuit  Breakers 84 

Switches,  Flush    113 

Switches,  for  Room,   Convenience 164-165 

Switches,  Knife,  Installation  of 111-113 

Switches,  Knife,  Specifications   108-110 

Switch,  Master  165 

Switches,  Motor    167 

Switches,  Pilot,  Where  Used 167 

Switches,  Snap 113-114 

Symbols,  Used  for  Wires,  Outlets,  Fixtures, 

Etc ....188-190 

Tables,  See  Index  on  Page.  .  , 223 

Tables,  for  Dimensions,  Capacities,  Etc 223 

220 


Telegraph  and  Telephone  Wires 44 

Terms,  Electrical,  Definition  of 194-196 

Transformers,  Bell  Ringing,  Location 188 

Transformers,  Light  &  Power,  Installation.   44,  49 

Underground  Wiring    .  . 61 

Units,  Electrical,  Definition  of 194,  200-201 

Voltage,  in  House  Wiring 148 

Voltage,  Loss  in  Conductors 163 

Wrhen  in  Doubt 190 

Wire,   Con 96 

Wire,  for  Resistance  Use 161 

Wires,  and  Cable,   Splicing 68 

Wires,  Carrying   Capacity    68,  81 

Wires,  Dimensions  (See  Tables) 222 

Wires,  Entrance,  Main  Switch  and  Meters.  .        149 

Wires,  For  Outside  Use 54 

Wires,  Installation  of,  Open  Work 79-84 

Wires,  Insulation 66-67 

Wrires,  Line 39 

Wires,  List  of  Approved  Makers 66-67 

Wires,  Protection  on  Walls 80 

Wires,  Rubber  Covered    66 

Wires,  Service    39,  42 

Wires,  Slow-Burning  and  Weatherproof  ...         67 

.Wires,  Stranded .69,  103 

Wires,  Tie 39 

Wires,  Tie,  Inside   68 

Wires,  To  Find   Proper  Size 69 

Wires,  Twin    80 

Wiring,  Alternating  Current  (A.  C.) 70-78 

Wiring,  Car  House   133 

Wiring,  Cleat  Work,  Open   159 

221 


Wiring,  Concealed    90 

Wiring,  Conduit 91 

Wiring,  Costs,   Approximate    160-161 

Wiring,  in  Fixtures 100 

Wiring,  Inside,    General    Suggestions 66 

Wiring,  Flexible   Cord    100-101 

Wiring,  for   High   Voltage 56-57 

Wiring,  for  Telephone  and  Bell  Service.  .  .  .        162 
Wiring,  for    Telephone    and    Bell,    Sugges- 
tions  186-189 

Wiring,  from  Generators  and  Switchboards  7 

Wiring,  from  Service  Mains  to  House.  .  .  .143-146 

Wiring,  Primary   A.   C 60 

Wiring,  Special  for  Damp  Places 87 

Wires,  Strength  of 82 

Wiring,  Suggestions  for  Hall  and  Vestibule       166 
Wiring,  Suggestions      to      Architects      and 

Owners    141-190 

Wiring,  Support  in  Conduits 97 

Wiring    Tables,  (See  Tables)    222 

Wiring,  Through  Walls,  Floors,  Etc.. 80-84 

Wiring,  Tree 42 

FORMULAE. 

To  Find : 

Belting,  Proper  Length  and  Strength 166 

Circulars  Mils,  Size  of  Wire 197 

Current,  in  Amperes,  D.  C 197 

Current  Required,  for  D.  C.  Motors f     30 

Efficiency,  Lamps,  Motors,  Etc 198 

Engines,  Steam,  Horse-power .  .213-214 

Ohms  Law,  All  Values  for  D.  C 196-197 


Pulleys,  Proper  Sizes   215 

Resistance,  in  Ohms,  D.  C 198 

Shafting,  Iron  and  Steel,  Proper  Size 212-213 

Voltage,  Electromotive  Force,  D.  C 198 

Watts,   Per  .Candle-power 199 

Weight  of  Copper  and  Iron  Wire. 199 

Wire,  Size  for  i -phase,  2-wire    77 

Wire,  Size  for  I -phase,  3-wire 78 

Wire,  Size  for  2-phase,  3-wire,  Lighting  .  .         75 
Wire,  Size  for  3-phase,  3-wire,  Motor  ....          73 

Wire,  Size  of,  for  A.  C.,  General 73-?8 

Wire,  Size  of,  for  D.  C.  Motors.  . 29 

TABLES. 

Amperes  per  Motor,  A.  C 72 

Amperes,  per  Motor,  D.  C 31 

Cables,   Armored,   Makers   of 101 

Cables,  Stranded,  Rubber  Covered,  Dimen- 
sions           208 

(  ables,  Stranded,      Weatherproof ,      Dimen- 
sions           206 

Conduit,  Sizes    for    i,    2  and    3    Wires,    or 

Cables    202-203 

Conduit,  Underground,  Fibre,  Dimensions.  .       204 

Efficiency,   Motors,   D.    C 29,  31 

Fuses,  Approved  Enclosed,  Dimensions.  . .  .125-126 

Fuses,  Enclosed,   Approved  Makers 124 

Fuses,  Open  Link,  Dimensions 122 

Fuses,  Size  of,  for  Motors,  (A.  C.) 72 

Fuses,  Size  of,  for  Motors,  (D.  C.) 30 

Insulation,  of  Wiring  in  Buildings 107-108 

Lamps,  Carbon,  Gem,  Mazda,  Tungsten.  .  115-116 

293 


Lamps,  Mercury  Vapor  (Cooper  Hewitt)..        117 

Lamps,  Variations   with  Voltage 116 

Light,  Cut  Off  by  Various  Glass  Globes.  ...       215 

Poles,  Cedar,  Size  and  Weight .         61 

Poles,  No.  per  Mile  and  Distance  Between.  .  62-63 

Switches,  Knife,  Dimensions no 

Symbols,  for  Wiring  Plans 189-190 

Unit-s,  Electrical  and  Power,  Values 200-201 

Volts  Lost  at  Different  Per  Cent.  Drop 32 

Wire,  Approved  Rubber  Covered,  Makers.  .  66-67 

Wire,  Bare  Copper,  Strength  of 82 

Wire,  Carrying  Capacity,  Dimensions,  Etc.  .         81 

Wire,  Current  Required  to  Fuse 127 

Wire,  Equivalent  Cross  Sections 82 

Wire,  Insulation  Thickness 66-67 

Wire,  Iron,  Steel,  Copper,  Comparative.  .  .  .  210 
Wire,  Magnet,  Fine,  Resistance  and  Weight  209 
Wire,  "Phono-Electric"  and  Hard  Drawn, 

*  Comparative   Strength    211 

Wire,  Proper   Size    for   Currents   and   Loss 

in  Volts 70,  74,  76 

Wire,  Resistance  and  Weight,  per  1000  feetSi,  137 
Wire,  Rubber  Covered,  Solid,  Dimensions .  .  207 

Wire,  Size  for  A.  C.  Systems 70-76 

Wire,  Supporting  Distance  in  Conduits. ...         97 
Wire,  Weatherproof,    Solid,    Dimensions... 
Wire,  Weatherproof,  Weight  Between  Poles  62-63 
Wiring  Costs,  Approximate,   House 160 


224 


CLASSIFIED    INDEX 

MANUFACTURERS  OF 
OFFICIALLY   APPROVED   APPARATUS   AND   SUPPLIES 

(See  Pages  4   and  5  for  Addresses) 


ADJUSTERS,  LAMP   CORD 
Trumbull  Electric  Mfg.   Co. 

AMMETERS  AND  VOLTMETERS 
General  Electric  Co. 
Hoyt   Elecl.    Inst.    Co. 
L.  M.   Pignolet 

Westinghouse  Elec.  &  Mfg.   Co. 
Weston    Elecl.    Inst.    Co. 

ASBESTOS 

H.  W.  Johns-Manville  Co. 

ATTACHMENT  PLUGS 

Bryant  Electric  Co. 
Cutler-Hammer  Mfg.  Co. 
General  Electric  Co. 
Pass  &  Seymour,  Inc. 
Trumbull   Elec.   Mfg.  Co. 

AUTO-STARTERS 

Cutler-Hammer  Mfg.  Co. 
General  Electric  Co. 
Monitor  Controller  Co. 
Westinghouse  Elec.   &  Mfg.   Co. 

BOOKS,    ELECTRICAL 

John  Wiley  &   Son,   Inc. 

BUSHINGS,    PORCELAIN 

General  Electric  Co. 
Pass    &    Seymour,    Inc. 

CABINETS 

Frank  Adam  Electric  Co. 
Bryant  Electric  Co. 
General  Electric  Co. 
Post-Glover    Electric    Co. 
Sprague  Elec.  Wks.  of  G.  E.  Co. 
Trumbull  Elec.    Mfg.    Co. 

CABLES,   ARMORED 

National   Metal   Molding  Co. 
Safety-Armorite    Conduit    Co 
Sprague  Elec.  Wks.  of  G.  E.  Co. 
Western  Conduit  Co. 

CANOPY    INSULATORS 

General  Electric  Co. 
The   Macallen  Co. 

CIRCUIT  BREAKERS 

Condit  Elecl.   Mfg.    Co. 
Cutter  Electric  &  Mfg.  Co. 
General  Electric  Co. 
Westinghouse  Elec.  &  Mfg.  Co. 


CLEATS,    &  KNOBS,   PORCELAIN 

Cook   Pottery   Co. 
General  Electric  Co. 
Pass  &  Seymour,  Inc. 

COMPOUNDS,  INSULATING 

Walpole  Tire  &  Rubber  Co. 

CONDUIT,    FLEXIBLE,   NON- 
METALLIC 

Alphaduct  Company 
American   Circular   Loom  Co. 
American    Conduit    Mfg.    Co. 
National  Metal  Molding  Co. 
Tubular  Woven  Fabric  Co. 

CONDUIT,  FLEXIBLE  STEEL 
National  Metal  Molding  Co. 
Safety-Armorite  Conduit  Co. 
Sprague  Elec.  Wks.  of  G.  E.  Co. 

CONDUIT,  RIGID  METAL 

American  Circular  Loom  Co. 
American  Conduit  Mfg.  Co. 
National  Metal  Molding  Co. 
Safety-Armorite  Conduit  Co. 
Sprague  Elec.  Wks.  of  G.  E.  Co. 
Western  Conduit  Co. 

CONDUIT  BOXES 

Frank  Adam  Electric  Co. 
Chicago  Fuse  Mfg.   Co. 
Gillett-Vibber  Co. 
Sprague  Elec.  Wks.  of  G.  E.  Co. 

CONNECTORS,  SOLDERLESS 

Dossert  &  Company 

CURRENT  TAPS 

Bryant  Electric  Co. 
General  Electric  Co. 

CUT-OUT  BASES 

(For  Edison  Plug  Type  Fuses) 
Bryant   Electric  Co. 
General  Electric  Co. 
Trumbull  Elec.  Mfg.  Co. 
Westinghouse  Elec.  &  Mfg.   Co. 

CUT-OUT  BASES 

(For  inclosed   fuses) 
Bryant   Electric  Co. 
Chicago    Fuse   Mfg.   Co. 
D  &  W  Fuse  Co. 
General  Electric  Co. 
H.  W.  Johns-Manville  Co. 


Trumbull  Elec.  Mfg.  Co. 
Westinghouse    Elec.    &    Mfg.    Co. 

EXTINGUISHERS,  FIRE 
Pyrene   Manufacturing  Co. 

FIXTURES,   ELECTRIC 
Frank  Adam  Electric  Co. 
Gas  Fixture  &  Brass  Co. 
Post-Glover   Elec.   Co. 
Wakefield  Brass   Co. 


INSULATORS,  POLE  LINE 
Brookfield  Glass  Co. 
Hemingray    Glass    Co. 

KNOBS  &  CLEATS,  PORCELAI] 
Cook  Pottery  Co. 
General    Electric  Co. 
Pass  &  Seymour,  Inc. 

LAMP   CLUSTERS 
Luminous  Unit  Co. 


FLEXIBLE  CORDS 
(See  Wires) 

FUSES,  ENCLOSED 
Bryant   Electric  Co. 
Chicago  Fuse  Mfg.  Co. 
Condit    Elecl.    Mfg.    Co. 
Detroit   Fuse  &  Mfg.  Co. 
D  &  W  Fuse  Co. 
General  Electric  Co. 
H.  W.  Johns-Manville  Co. 
Westinghouse  Elec.  &  Mfg.  Co. 

FUSES,  PLUG  TYPE,   EDISON 

Bryant   Electric  Co. 

Chicago  Fuse  Mfg.  Co. 

D  &  W  Fuse  Co. 

General   Electric  Co. 
'    H.  W.  Johns-Manville  Co. 

FUSES,  OPEN  LINK 
Condit   Elecl.   Mfg.   Co. 
Chicago  Fuse  Mfg.  Co. 
General   Electric  Co. 
Walker    Electric    Co. 
Westinghouse  Elec.  &  Mfg.  Co. 

GAUGES,   WIRE 

Novelty  Electric   Co. 

GENERATORS 
(See  Motors) 

GROUND  CLAMPS 

Condit   Elecl.    Mfg.   Co. 

Fairmount  Elec.  Mfg.  Co. 

General    Electric  Co. 

Gillette-Vibber  Co. 

Hart   Mfg.  Co. 

Novelty  Electric  Co. 

Sprague  Elec.  Wks.  of  G.  E.  Co. 

HANGER  BOARDS,  ARC 
Bryant   Electric   Co. 
General   Electric  Co. 

HEATERS,    ELECTRIC 

(Soldering  and  Flat  Irons) 
Cutler-Hammer  Mfg.  Co. 
General   Electric  Co. 
Westinghouse  Elec.  &  Mfg.  Co. 

INSULATING  JOINTS 
The  Macallen  Co. 
Trumbull  Elec.  &  Mfg.  Co. 


LAMPS,  INCANDESCENT 
Buckeye   Electric  Division 
General  Electric   Co. 
Lux  Mfg.  Co. 

National  Lamp  Wks.  of  G.  E.  C 
Westinghouse  Elec.  &  Mfg.  Co. 

LAMPS,  MERCURY  VAPOR 
Cooper  Hewitt   Elec.   Co. 

LAMP    CLUSTERS 

General  Electric   Co. 

LIGHTNING  ARRESTERS 
Electric  Service  Supplies  Co. 
General  Electric  Co. 
Westinghouse  Elec.  &  Mfg.   Co. 

"MEGGERS" 

(For  Measuring  Resistance) 
James  G.  Biddle 

METERS,  WATT 
General  Electric  Co. 
Westinghouse  Elec.  &  Mfg.  Co. 

MOTORS 

Emerson   Elec.   Mfg.   Co. 
General  Electric  Co. 
Robbins  &  Myers  Co. 
Sprague  Elec.  Wks.  of  G.  E.  Co 
Westinghouse  Elec.  &  Mfg.  Co. 

MOTORS,    FAN 
(See  Motors) 

MOULDING,  METAL 

American   Circular   Loom   Co. 
National  Metal  Molding  Co. 

PANEL  BOARDS 

Frank  Adam   Electric  Co. 
Bryant   Electric  Co. 
General  Electric  Co. 
Post-Glover   Electric   Co. 
Sprague  Elec.  Wks.  of  G.  E.  Co. 
Trumbull   Elec.  Mfg.   Co. 
Walker  Electric  Co. 

RECEPTACLES 
Bryant   Electric  Co. 
General  Electric  Co. 
Pass  &  Seymour,  Inc. 
TrumbuU  Elec.  Mfg.  Co. 


RTIEOSTATS 

Cutler-Hammer  Mfg.   Co. 
General  Electric  Co. 
Monitor  Controller  Co. 
Sprague  Elec.  Wks.  of  G.  E.  Co. 
Westinghouse  Elec.   &  Mfg.  Co. 

ROSETTES 

Bryant   Electric  Co. 
General   Electric   Co. 
Pass  &  Seymour,  Inc. 
Trumbull  Elec.  Mfg.  Co. 

SOCKETS,   STANDARD 

Rryant   Electric  Co. 
General   Electric   Co. 
Pass  &  Seymour,  Inc. 

SOCKETS,    PORCELAIN 

Bryant   Electric  Co. 
Cutler-Hammer  Mfg.    Co. 
General   Electric   Co. 
Pass  &  Seymour,  Inc. 

SOCKETS,    WEATHERPROOF 

Bryant   Electric  Co. 
General   Electric   Co. 
H.  W.  Johns-Manville  Co. 
Pass  &   Seymour,  Inc. 
Trumbull  Elec.  Mfg.  Co. 

SOLDERING  FLUX 

Burnley  Battery  &  Mfg.    Co. 
M.    W.    Dunton   Co. 

SOLDERING  IRONS 

Vulcan  Electric   Heating   Co. 

SWITCHBOARDS 

(See   Switches,    Knife) 

SWITCH  BOXES 
Bryant   Electric  Co. 
Chicago  Fuse  Mfg.  Co. 
Cutter  Elecl.  &  Mfg.   Co. 
Detroit   Fuse  &  Mfg.  Co. 
General    Electric   Co. 
Hart  Mfg.  Co. 
H.  W.  Johns-Manville  Co. 
Machen  &  Mayer  Elecl.  Mfg.  Co. 
Sprague  Elec.  Wks.  of  G.  E.  Co. 

SWITCHES,  AUTOMATIC,  TIME 
Reliance   Automatic   Lighting  Co. 

SWITCHES,   KNIFE 
Frank  Adam  Electric   Co. 
Bryant   Electric  Co. 
General    Electric   Co. 
Post-Glover  Elec.  Co. 
Trumbull  Elec.  Mfg.  Co. 
Walker  Electric  CD. 
Westinghouse  Elec.  &  Mfg.  Co. 

SWITCHES,    OIL    BREAK 

Condit  Elecl.  Mfg.  Co. 
General    Electric   Co. 
Westinghouse  Elec.  &  Mfg.  Co 


SWITCHES,  SNAP 

Bryant  Electric  Co. 
Cutler-Hammer  Mfg.  Co. 
General    Electric   Co. 
Pass  &  Seymour,  Inc. 
Trumbull  Elec.  &  Mfg.  Co. 

SWITCHES,  FLUSH,  PUSH 
Bryant  Electric  Co. 
Cutler-Hammer  Mfg.  Co. 
Cutter  Elecl.  &  Mfg.   Co. 
General   Electric  Co. 
Hart  Mfg.  Co. 
Machen  &  Mayer  Elecl.   Mfg.  Co. 

SWITCHES,  FLUSH,  ROTARY 

Bryant  Electric  Co. 
General  Electric  Co. 
Hart  Mfg.  Co. 

TAPE,  FRICTION,  INSULATING 
M.  W.  Dunton  Co. 
The  Okonite  Co. 
Walpole  Tire  &  Rubber  Co. 

TRANSFORMERS,    LIGHT    AND 
POWER 

General  Electric  Co. 
Westinghouse  Elec.  &  Mfg.  Co. 

TRANSFORMERS,  BELL  RINGING 

General  Electric  Co. 
Westinghouse  Elec.  £  ?vlfg.  Co. 

VEHICLES,  ELECTRIC 
General    Vehicle    Co.,    Inc. 

WIRE,    BARE,    COPPER 

Bridgeport  Brass  Co. 

Phillips  Ins.  Wire  Co. 

John  A.  Roebling's   Sons  Co. 

WIRE,  RUBBER  COVERED 

American  Electrical  Works 
American  Steel  &  Wire  Co. 
Atlantic  Ins.  Wire  &  Cable   Co. 
Bishop  Gutta-Percha  Co. 
Electric   Cable   Co. 
General  Electric  Co. 
Habirshaw  Wire  Co. 
Indiana  Rubber  &  Ins.  Wire  Co. 
Kerite  Ins.  Wire  &  Cable  Co. 
Lowell  Ins.  Wire  Co. 
National  India  Rubber  Co. 
The  Okonite  Co. 
Phillips  Ins.  Wire  Co. 
John  A.  Roebling's  Sons  Co. 
Rome   Wire    Co. 
Simplex  Wire  &  Cable  Co. 
Standard  Underground  Cable  Co. 

WIRE,   FLEXIBLE   CORD 

(See  Wire,  Rubber  Covered) 

WIRE,    SLOW-BURNING 

American  Electrical  Works 
American  Steel  &  Wire  Co. 
Chicago  Ins.  Wire  Co. 


General  Electric  Co.  Chicago  Ins.  VVire  Co. 

Phillips  Ins.  Wire  Co.  General  Electric  Co. 

John  A.  Roebling's  Sons  Co.  National  India  Rubber  Co. 

Standard  Underground  Cable  Co.  Phillips  Ins.   Wire  Co. 

John  A.  Roebling's  Sons  Co. 

WIRE,  SLOW-BURNING  WEATH-  Simplex  Wire  &  Cable  Co. 

ERPROOF  Standard  Underground  Cable  Co. 
Chicago  Ins.  Wire  Co. 

General  Electric  Co.  WIRE,   "PHONO-ELECTRIC1' 

Bridgeport  Brass  Co. 
WIRE,  WEATHERPROOF 

American  Electrical  Works  WIRE,   RESISTANCE 

American    Steel   &   Wire   Co.  Driver-Harris  Wire  Co. 


List  of  Advertisers  of  Standard  Apparatus  and  Supplies 

Only    Apparatus    and    Supplies    that    are    officially    approved,    or  per- 
mitted   to    be    used,    by    the   National   Board    of   Fire    Under- 
writers  will   be   accepted   in    the  following  pages. 

ADAM    ELECTRIC    CO.,    FRANK 4<; 

ALPHADUCT     CO 56 

AMERICAN    BRASS    CO 42 

AM.    CIRCULAR   LOOM    CO 57 

AMERICAN"  CONDUIT    MFG.    CO 55 

AMERICAN  ELECTRICAL  WO;RKS 36 

AMERICAN    STEEL  &  WIRE   CO 43 

ATLANTIC    INS.    WIRE   &    CABLE    CO 38 

BIDDLE,    JAMES    G 47 

BISHOP  GUTTA-PERCHA   CO 29 

BRIDGEPORT   BRASS   CO 40 

BROOKFIELD    GLASS    CO 22 

BRYANT     ELECTRIC     CO 67 

BUCKEYE    LAMPS 61 

BURNLEY   BATTERY   &   MFG.    CO 64 

CENTURY    ELECTRIC    CO... 93 

CHICAGO    FUSE    MFG.    CO 74 

CHICAGO  INS.   WIRE  &  MFG.  CO 31 

CONDIT    ELECL.    MFG.    CO 76 

COOK    POTTERY    CO 63 

COOPER   HEWITT   ELECTRIC   CO 14 

CUTLER-HAMMER    MFG.    CO 19 

CUTTER    CO.,    THE 12  &  13 

D    &   W    FUSE    CO 73 

DETROIT   FUSE   &   MFG.    CO 75 

DOSSERT    &    CO 52 

DRIVER-HARRIS     WIRE     CO 71 

DUNTON    CO.,    M.    W 81 

ELECTRIC    CABLE    CO 32 

ELECTRIC   VEHICLE   HAND-BOOK 82 

ELBLIGHT    CO.    OF    AMERICA 92 

ELECTRIC    SERVICE    SUPPLIES    CO 62 

EMERSON    ELECTRIC    MFG.    CO 20 

4 


FRANKLIN    STEEL   WKS 90 

GAS    FIXTURE    &    BRASS    CO 85 

GENERAL    ELECTRIC    CO 10  &  11 

GENERAL    VEHICLE    CO 70 

GILLETTE- VIBBER     CO 78 

HABIRSHAW     WIRE     CO 25 

HART     MFG.     CO 45 

IIASKINS   GLASS   CO 91 

HEMINGRAY     GLASS     CO 23 

HOYT    ELECL.    INST.    CO 51 

INDIANA   RUBBER    &    INS.    WIRE    CO 30 

JOHNS-MANVILLE    CO.,    H.    W 72 

KERITE   INS.   WIRE   &   CABLE   CO 26 

LOWELL    INS.    WIRE    CO 35 

LUX     MFG.     CO 65 

MACALLEN     CO.,     THE 16,  17  &  18 

MACHEN  &  MAYER  ELECL.   MFG.   CO 44 

MASS.    ELEC.    MFG.    CO, 98 

MONITOR   CONTROLLER  CO 79 

MORGAN    CRUCIBLE  •  CO 89 

NATIONAL    INDIA   RUBBER    CO 41 

NATIONAL   LAMP   WKS.,   OF   G.    E.    CO 7 

NATIONAL    METAL    MOLDING    CO 60 

XOVELTY    ELECTRIC    CO 53 

THE     OKONITE     CO 27 

OTTO    GAS    ENGINE    WKS... 99 

PASS    &    SEYMOUR,    INC 77 

PHILLIPS.    INS.    WIRE    CO 34 

PHOENIX    GLASS    CO 88 

PIGNOLET,    L.    M 50 

POST-GLOVER   ELECTRIC   CO 66 

P YRENE    MFG.    CO 100 

RELIANCE  AUTOMATIC  LIGHTING  CO 24 

ROBBINS    &    MYERS    CO 21 

ROEBLING'S    SONS    CO.,    JOHN    A..' 28 

ROME    WIRE    CO 37 

SAFETY-ARMORITE    CONDUIT    CO 54 

SIMPLEX  WIRE  &  CABLE  CO 39 

SIMPLEX  TIME  RECORDER  CO 84 

SPRAGUE    ELECTRIC    WKS.,    OF    G.    E.    CO 8&9 

STANDARD    UNDERGROUND    CABLE    CO 33 

STAR   EXPANSION    BOLT    CO 83 

STAR    PORCELAIN    CO 86 

TRUMBULL  ELEC.   MFG.    CO 49 

TUBULAR   WOVEN  FABRIC  CO 58 

VULCAN    ELEC.    HTG.    CO 87 

WAKEFIELD   BRASS   CO.,   F.   W 68 

WALPOLE  TIRE  &  RUBBER  CO 69 

WALKER    ELECTRIC    CO 15 

WESTERN    CONDUIT    CO 59 

WESTINGHOUSE  ELECTRIC  &  MFG.   CO 6 

WESTON   ELECL.   INSTRUMENT   CO 48 

WILEY  &   SON,   INC.,   JOHN 80 

5 


Westinghouse 

Switchboards 


'THE  use  of  Westinghouse  7-inch  Meters  permits  the 
panels  of  this  board  to  be  only  16-inches  wide. 

The  wiring  at  rear  of  board  is  complete.  When  in- 
stalling it  is  only  necessary  to  connect  the  cables  to  the 
terminals  provided,  and  everything  is  ready  for  imme- 
diate operation. 

The  panels  illustrated  control  a  motor-generator  set 
consisting  of  a  2200  volt  Westinghouse  synchronous 
Motor  and  a  275  volt  Westinghouse  Direct-Current  Gen- 
erator for  mining  service. 

These  boards  can  be  shipped  "rom  stock  in  all  usual 
capacities. 

Westinghouse  Electric  &  Mfg.  Co. 


Sales  Offices  in 
All  Large  Cities 


East  Pittsburgh 
Pennsylvania 


IT  ME      dJTLJA  LIT  Y      JL  A  M  3»  MIAEJIE      C  KI      A  MI  E  K I C  A 

WHEN  you  take  a  customer's  money  in  ex- 
change for  a  lamp  you  are  the  one  he 
holds   responsible   for   its   quality.     The 
reputation  of  your  house  will  profit  or  suffer  in 
degree  according  to  the  kind  of  service  that  lamp 
will  give.    When,  therefore,  you  place  your  name 
back  of  National  MAZDA  Lamps,  you  are  per- 
fectly  justified   in   demanding   an   assurance   of 
their  high  quality. 

National  MAZDA  lamp  quality  is  founded  on 
the  technical  knowledge  of  experts.  National 
MAZDA  lamps  are  the  culmination  of  years  of 
effort  on  the  part  of  the  Research  and  Develop- 
ment Laboratories  of  the  General  Electric  Com- 
pany at  Schenectady  and  Cleveland — laboratories 
that  have  access  to  every  improvement  produced 
in  other  leading  laboratories  of  the  world. 

But  just  as  important  as  this  basis  of  National 
Quality  is  the  maintenance  of  that  quality  by 
careful  methods  of  manufacture,  by  a  rigid  in- 
spection of  all  raw  materials,  by  a  constant  test- 
ing of  product  and  by  a  vigilant  lookout  for 
improvements  that  will  still  further  raise  the 
standard  of  quality. 

From  factory  to  socket  National  MAZDA  lamps 
mean  satisfaction. 


Nela  Park,  Cleveland 

Member  Society  for  Electrical  Development  —"Do  it  Electrically" 


SPRAGUE  FLOOR  BOXES 

Adjustable.  Non-Adjustable.  Adjustable   Gang. 

"ABSOiLyTELY    WATERTIGHT." 


Sectional  View  of 
No.  6650  Adjust- 
able  Floor  Box, 
Showing  Extreme 
Adjustment. 


No.    6860   Midget 

Non- Adj  ustable 

Floor  Box 


Sectional  View   of 

No.  6650 

Adjustable  Flooi 
Box  Showing  G. 
E.  Receptacle  No. 
GE700  and  Cap 
No.  49487  in  posi- 
tion. 


OUTLET  AND  SWITCH 
BOXES  AND  COVERS 


r 


No.    6200   Box   with   6206  No.     6350     Octagon     Box 

Canopy   Cover   with   Ears  with  6387  Pendant  Cover, 

Drilled   and   Tapped.  ^"  Insulating  Bushing. 

SIMPLE    —  PRACTICAL 

Interchangeable    with    Boxes    and   Covers    of   other    manufacture 
Clean   cut   knockouts 

FITTINGS  AND  TOOLS 


SPRAGUE 


ELECTRIC  WORKS 

OF  GENERAL   ELECTRIC   COMPANY 

Main   Offices:    527-531    West   34th   Street 
New   York,    N.  Y. 

Branch  Offices  in   Principal  Cities 


TRADEMARK 


SPRAGUE  BX  CABLE 


UEG.U3.PAT.OFF. 


Hot    Galvanized    Flexible    Steel    Armored    New    Code    Insulation — 
Distinguishable    Braids. 


GREENFIELD  CONDUIT 


Flexible  Steel 


Conduit   with    Coupling 

The    Most   Practical  Form  of  Well  Galvanized  Unlined  Metallic 
Conduit    on    the    Market. 


GREENFIELDUCT 


The    Only    Hot    Galvanized    Rigid    Iron    Conduit — The    Standard    by 
Which   All   Other   Galvanized   Conduits  Are   Compared 


SPRAGUE 


ELECTRIC  WORKS 

OF   GENERAL  ELECTRIC   COMPANY 
Main   Offices:    527-531    West   34th    Street 
New   York,    N.  Y. 

Branch  Offices  in  Principal  Cities 


A  Device  for  Every  Use 


A  few  devices  illustrating  the  great  variety  of  G-E  wiring  supplies 
are  shown  in  the  above  group.  A  complete  stock  of  G-E  reliable 
wiring  devices  includes  every  device  for  use  in  making  installations 
or  extending  lighting  or  power  lines  in  factories,  stores,  restaurants 
places  of  amusement  or  homes.  In  fact,  all  that  is  required  by 
the  up-to-date  electrical  contractor  will  be  found  in  a  G-E  assortment. 

The  careful  construction  of  G-E  Wiring  Supplies  insures  absolute 
reliability.  This  careful  construction,  together  with  excellence  of 
design  and  quality  of  material,  result  in  a  completed  product  fulfill- 
ing all  requirements  of  the  National  Board  of  Fire  Underwriters 
for  electric  wiring. 

Electrical  contractors  and  electricians  should  specify  G-E  material 
for  all  electrical  work  under  their  direction.  The  large  G-E  assort- 
ment meets  every  wiring  need,  making  standardization  easy  and 
insuring  the  highest  possible  quality  throughout,  coupled  with  per- 
manent satisfaction. 

G-E  Wiring  Devices  are  for  sale  by  all  leading  jobbers  of  electrical 
material. 

General  Electric   Company 

Largest  Fltctrical  Manufacturers  in  the  World 

Atlanta,  Ga.  General   Office:     Schenectady,    N.   Y.  Omaha,  Neb. 

Baltimore,  Md  ADDRESS    NEAREST  OFFICE  2£SjS?pk  F 

Birmingham,   Ala.     S1"8,^,8'  A± 


Boston,  Mass. 

Buffalo,  N.  Y. 

Butte,  Mont. 

Charleston,  W.  Va. 

Charlotte,  N.  C. 

Chattanooga,  Tenn.   Duluth,  Minn. 

Chicago,  111.  Elmira,  N.  Y. 

Cincinnati,  Ohio.        Erie,  Pa. 

Cleveland,  Ohio 

Columbus,  Ohio 

Dayton,  Ohio 


Portland,  Ore. 
Providence.    R.   I. 
Richmond,  Va. 
Rochester,   N.  Y. 
San  Francisco,  Cal. 
Salt  Lake  City, 

Utah 

St.  Louis,  Mo. 
Schenectady,  N.  Y. 


Louisville,  Ky. 
Memphis,  Tenn. 
Milwaukee,  Wls. 

Fort  Wayne,  Ind.    Minneapolis,  Minn.     Seattle,  Wash. 
Indianapolis,  Ind.  Nashville,  Tenn.          Spokane,   Wash. 
Jacksonville,  Fla.    New  Haven,   Ct.          Springfield,    Mass. 
Denver.  Colo.  Joplin,  Mo.  New   Orleans,    L*.      Syiacuse,    N.    Y. 

Des  Molnes,  la.  Kansas  City,  Mo.     New  York.   N.   Y.      Toledo,  Ohio 

Detroit,  Mich.  Knoxville,  Tenn.  '   Niagara  Falls.  Washington,   D.   C. 

(Office  of  Agent)        Los  Angeles,  Cal.  N.  Y.     Youngstown,    O'hio 

For  Texas,  Oklahoma  and  Arizona  business  refer  to  Southwest  General  Elec- 
tric Company  (formerly  Hobson  Electric  Co.),  Dallas,  El  Paso,  Houston,  and 
Oklahoma  City.  For  Canadian  business  refer  to  Canadian  General  Electric 
Company,  Ltd.,  Toronto,  Ont.  4&24 

MEMBER  THE  SOCIETY  FOR   ELECTRICAL  DEVELOPMENT,   INC.— "DO 
IT  ELECTRICALLY" 


10 


G-E  Reliable 
Wiring  Devices 


Adjustable    Terminal    Ground 
Clamps 

Attaching  Plugs 

Automobile      Wiring      Acces- 
sories 

Cable  Connectors  and  Plug 
Couplings,  Push  Button 
Switches,  Sockets  and  Re- 
ceptacles, Snap  Switches, 
Hand  Searchlight,  Battery 
Charging  Plug  and  Recep- 
tacle, Cutouts,  Glass  Tube 
Fuses. 

Boards 

Arc  Lamp  Ceiling,  Pilot 
Lamp  Connector,  Buzzer, 
Alternating  Current;  Buzzer, 
Combined  Switch  and 

Connectors 

Cord,    Three-heat. 

Cutouts 

Combined  Switch  and  Plug, 
Electrolier,  Enclosed  Fuse, 
250  Volt;  Enclosed  Fuse, 
600  Volt;  Enclosed  Fuse, 
2500  Volt. 

Fuses 

Enclosed,  Link,  Plug,  Plug 
and  Reloads,  Potential,  Train 
Control  Equipment,  Fuse 
Wire,  Fuse  Clips  and  Ter- 
minals. 

Insulators 

Porcelain    Clamp,    Rack,    In- 

,  sulator  Racks,  Iron  Boxes 
with  Cutouts,  Knockdown 
Panel  Circuits,  Knockdown 
Panel  Circuit  Parts,  Lamp 
Guards,  Portable. 

Lever  Switches 

Miniature,  Motor  Starting 
and  Running,  Punched  Clip, 
Type  L  Form  D12,  Type  Q 
Form  C2. 

Plugs 

Attaching,  Combined  Socket 
and  _  Separable  Attaching, 
Combined  Switch  and  Sepa- 
rable Attaching.  Fuse  Minia- 
ture Swivel,  Miniature  Sep- 
arable, Separable  Attaching, 


Socket,  Swivel,  Porcelain 
Specialties. 

Receptacles 

Automobile,  Conduit,  Con- 
duit Box,  Double  Door 
Flush,  Indicating  and  Test- 
ing Lamp,  Machine  Shop, 
Marine,  Metal  Shell,  Minia- 
ture and  Candelabra,  Porce- 
lain, Quick  Make  and 
Break — 660  Watts,  Remov- 
able Flush  Wall,  Separable, 
Sign. 

Rosettes 

Fused   and   Fuseless. 

Snap  Switches 

Accessories  and  Cutouts, 
Ceiling,  Conduit,  Fan  Mo- 
tor, For  Automobile  Light- 
ing, Moulding,  Panel  Board, 
Pendent,  Porcelain,  Remote 
Control,  Series  Parallel, 
Small  Motor  Control,  With 
Extra  Deep  Bases,  600  Volt. 

Shadeholders 

Sockets 

Acorn  Shell,  Automobile, 
Candle,  Electrolier,  Exten- 
sion Kev.  Extra  Loner  Key, 
Socket  Handle  and  Adjuster, 
Brass  Shell,  Key  and  Kev- 
less;  Locking  Marine  Weath- 
erproof, Miniature  and  Can- 
delabra, Porcelain,  Key  and 
Kevless:  Pull,  Quick  Make 
and  Break  —  660  Watts, 
Series,  Special  Designs,  Spe- 
cial Finishes,  Three-Way, 
Weatherproof,  650  Volt. 

Socket  Handles  and  Adjusters 

Socket  Plugs  and  Bushings 

Socket  Rings 

Strips 

Battery,    Interconnection. 

Switches 

Flush     Push     Button,     Flush 
Rotary,  Lever,  Surface  Snap, 
Pendent. 
Terminals 

Fuse  Clips  and  Wrought 
Copper  Cable. 


General   Electric  Company 


See  facing  page 


3S4S 


' 


Flush  Plugs,  Screw  Plugs 
and  Flush  Switches 

The  Cutter  Co. 

PHILADELPHIA 


I-T-E 

Circuit  Breakers 

for  every  service 

The  next  time  a  fuse  blows  replace  it 
with  an  I-T-E  Circuit  Breaker. 

The  Cutter  Co. 

PHILADELPHIA 


Cooper   Hewitt  Light 

has  been  proving  for  ten  years  that  it 
is  equal  to  the  best  daylight  for  all  in- 
dustrial purposes,  and  "Better  Than 
Daylight"  for  many  purposes. 

It  is  free  from  glare  due  to  the  fact 
that  it  comes  from  a  long  tube  of  lumin- 
ous vapor,  not  from  a  small  glowing 
solid.  It's  soft  blue-green  color  is  rest- 
ful to  the  eyes,  being  free  from  the 
irritating  red  rays  radiated  from  every 
other  artificial  light.  It  casts  no  deep 
shadows. 

Cooper  Hewitt  Lamps  take  less  cur- 
rent, require  less  attention  and  cost  less 
for  upkeep. 

Read  our  Bulletin  4637  "Better  Than 
Daylight." 


Type  F  Cooper  Hewitt  Lamp  for  Alternating  Current  Circuits 
Made  for  either  25,  40,  50  and  60  cycles 

Cooper  Hewitt  Electric  Co. 

8th  and  Grand  Streets,  Hoboken,  New  Jersey 


Boston — 161  Summer  Street. 
Chicago — 215  Fisher  Bldg. 
Cincinnati — 1st  Nat.  Bank  Bldg. 
Cleveland — Engineers'   Bldg. 


Detroit— Ford  Building 
Philadelphia— 124  S.  8th  Street 
Pittsburgh — Westinghouse  Bldg. 
St.  Louis — Central  National  Bank 
Building 


/fa/n0  ofr- 


Panel  Boards 

Knife  Switches 
and 

Switchboard 

Accessories 


Walker    Electric   Company 

PHILADELPHIA 


MACALLEN 

ARMORED  MICA 
INSULATING  JOINTS 


This  ARMORED  Joint  is  the  result  of  over 
twenty  years'  experience  in  the  manufacture  of 
Insulating  Joints. 

It  has  the  greatest  mechanical  and  electrical 
strength,  and  is  ihe  most  compact  joint  ever 
made. 

These  joints  will  be  regularly  inspected  and 
labeled  under  the  supervision  of  the  Under- 
writers' Laboratories,  Inc.,  under  the  direction  of 
the  National  Board  of  Fire  Underwriters. 

The  Macallen  Company 

Macallen  &  Foundry  Streets 
Boston,  Mass. 

Catalogues  and  Price  Lists  Furnished  Upon  Application 

16 


MACALLEN 

Solid  Mica 

Insulating  Joints 


Regularly  inspected  and  labeled  under  the  su- 
pervision of  the  Underwriters'  Laboratories,  Inc.; 
under  the  direction  of  the  National  Board  of  Fire 
Underwriters. 

We  carry  a  large  stock  and  can  fill  all  orders 
promptly. 

The  Macallen  Company 

Macallen  &  Foundry  Streets 
Boston,  Mass. 

Catalogues  and  Price  Lists  Furnished  Upon  Application 


MACALLEN 

Canopy   Insulators 


Patented  July  13,  1897 

Regularly  inspected  and  labeled  under  the  su- 
pervision of  the  Underwriters'  Laboratories,  Inc., 
under  the  direction  of  the  National  Board  of  Fire 
Underwriters. 

They  are  designed  to  go  between  the  canopy  and 
the  wall  or  ceiling,  where  combination  or  straight 
electric  fixtures  are  installed  in  buildings  that  are 
constructed  with  metallic  lathing,  or  where  there 
are  metal  ceilings  or  walls  used. 

They  are  made  of  a  special  compound  that  is 
thoroughly  waterproof,  strong,  durable,  and  of  the 
highest  insulating  qualities. 

We  manufacture  these  insulators  to  fit  all  stand- 
ard sizes  of  canopies. 


The  Macallen  Company 

Macallen  &  Foundry  Streets 
Boston,  Mass. 

Catalogues  and  Price  Lists  Furnished  Upon  Application 

"  18 


CUTLER-HAMMER 


MOTOR  CONTROLLERS 

Hand  Operated  and  Automatic  Types 


Hand    Operated   Type 
Motor    Starter   with 
No  -  Voltage      and 
Automatic   Starter.  Overload     Release. 

Cutler-Hammer  Starters  and  Controllers  are  made  for  both  direct 
and  alternating  current  motors.  When  installing  motors  tell  us 
what  you  wish  to  accomplish  and  we  will  send  bulletin  describing 
just  the  apparatus  you  need. 

PUSH  BUTTON  SPECIALTIES 


No.   7109  Push  New    No.    7500  No.    7007 

Button   Snap   Switch  Brass    Shell  "Acorn"   Brass 

Push  Button  Socket  Shell  Pendent 

The   C-H  line  of     specialties   includes   Porcelain  and   Brass   Shell 
Pendent    Switches,   Sockets,   Surface   Switches,    Flash   Switches,  Fix- 
ture   Canopy    and    Candelabra    Switches.      Door    Switches,    besides    a 
complete  line  of  Attachment  Plugs  and  Attachment  Plug  Receptacles. 
Ask    for    Bulletin    8650. 

THE  CUTLER-HAMMER  MFG.  CO.,  Milwaukee 

Largest  Manufacturers  of  Electric  Controlling  Devices  in  the  World 

NEW    YORK  BOSTON  PITTSBURGH 

Hudson   Terminal         Columbian   Life  Bldg.   Farmers'  Bank  Bldg. 

CHICAGO  PHILADELPHIA  CLEVELAND 

Peoples    Gas     Bldg.  1201  Chestnut  St.  Schofield  Bldg. 

PACIFIC  COAST  AGENTS:     H.  B.  Squires,  579  Howard  St.,  San 
Francisco,  and  W.  B.  Palmer,  416  East  Third  St.,  Los  Angeles. 


Emerson  Small  Motors 

1/30  to  1/2  hp. 

For  Alternating  and  Direct 
Currents 


J7ZI 


Glutchless  Induction   Motors 

Clutch  Type  Induction  Motors 

Enclosed  Direct  Current  Motors 

Ventilated  Direct  Current  Motors 

A  hundred  types  regularly  carried  in  stock  at 
St.  Louis  and  New  York 

Special  Types  developed  for  any  purpose  where 
quantities  are  required 


Write  for  Printed  Matter 

The  Emerson  Electric  Mfg.  Co. 

2032  Washington  Ave.,      St.  Louis  Mo. 
50  Church  St.,     New  York  City 

-:-     Makers  of  Emerson  Fans     -:- 


Type    "K"    A.C.    Motor. 


Robbins  &  Myers  Motors 

and  "Standard"  Fans 


The  Robbins  &  Myers 
line  of  motors  includes 
sizes  from  1/40  to  15 
horse-power,  direct  current 
and  1/40  to  7^/2  horse- 
power, alternating  current 
for  all  services. 

In  sizes  from  1/40  to  l/2. 
^  horse-power  inclusive,  our 
direct  current  type  "N" 
motors  and  single-phase, 
type  "P"  alternating  current 
motors  can  be  supplied  with  the  frames  the  same  in  all 
important  dimensions  for  the  same  speeds  and  capacities. 

Our  line  of  direct  current  generators  includes  sizes 
ranging  from  54  to  10  kilowatts  capacity  with  plain  or  fly- 
wheel pulley  as  desired. 


"Standard"  Fans 
are  made  in  desk, 
bracket,  oscillating 
and  ceiling  types  in 
sizes  to  meet  all  re- 
quirements. They 
are  furnished  for 
operation  on  .  all 
commercial  direct 
and  alternating  cur- 
rent circuits. 


Model   11    Oscillator,    Bracket    Position. 


THE  ROBBINS  &  MYERS  COMPANY 

SPRINGFIELD,  O. 


New  York 
Philadelphia 


Cincinnati 
Cleveland 


Boston 
Chicago 


Rochester 
St.    Louis 


INSULATORS 


4000  volts 


THE  STANDARD  FOR 
OVER  50  YEARS 


FOR  LOW  AND 
HIGH  VOLTAGES 


WITH  OR  WITHOUT 
DRIP   POINTS 


The    Brookfield    Glass  Company 

2  RECTOR  STREET,  NEW  YORK 

BRANCH  OFFICE,  309  South  Desplaines  St.,  Chicago,  III. 


EVERY  STYLE 

FOR 
EVERY    SERVICE 


SPECIAL 
DESIGNS 
DEVELOPED 


CORRESPONDENCE 
INVITED 


No.  135 
10000   volts 


TRADE       MARK 


REGISTERED. 


**&&$$i'*$$3^'''<'j' s '*  " '  *  """*"  •->"•••  •"^i'Ws^^P^^Hpl 


No.  19,  Deep  Groove   No.    71,    High   Voltage 
Double  Petticoat.  Triple   Petticoat. 


No.  2  Cable, 
Double    Petticoat. 


For  years  the  name  "Hemingray"  has  been  synonymous,  not 
only  with  "glass  insulators,"  but  with  "good  glass  insulators." 
The  Hemingray  insulators  have  been  and  are  good  insulators,  be- 
cause they  have  been  and  are  of  good  design  and  material  sub- 
jected to  proper  processes  of  manufacturing,  including  especially 
perfect  annealing.  In  a  glass  insulator,  "good  design"  means  more 
than  proper  lines  electrically, — it  means  a  design  which  so  dis- 
tributes the  material  that  good  annealing  is  possible.  Given  such 
a  design  and  a  proper  proportioning  of  materials  (including  not 
too  much  cullet),  it  is  possible  to  obtain,  and  the  Hemingray  Glass 
Company  does  produce  a  completed  insulator,  every  part  of  which 
is  perfectly  annealed. 

Thorough  annealing  is  of  supreme  importance  in  a  glass  insulator, 
and  faults  which  have  been  found  against  glass  as  a  material  for 
line  insulators  have  been  due  to  the  past  practice  of  some  other 
manufacturers  who  not  only  have  used  improper  annealing  methods, 
or  material  which  was  practically  incapable  of  being  properly  an- 
nealed, but  also  have  accepted  for  manufacture  certain  designs 
of  insulators  which  so  distributed  the  material  as  to  make  proper 
annealing  practically  impossible,  no  matter  what  materials  or 
methods  were  used.  The  HEMINGRAY  GLASS  COMPANY  has 
followed  as  one  of  its  first  principles  the  practice  of  not  accepting 
for  manufacture  any  design  which  their  sixty-five  years  of  experi- 
ence would  indicate  could  not  be  properly  and  perfectly  annealed. 
This  is  the  prime  reason  for  the  uniform  success  of  the  Hemingray 
insulator;  the  reason  for  its  superior  mechanical  quality  of  strength 
and  capabilities  to  withstand  the  shocks  of  sudden  blows  or  rapid 
and  extreme  temperature  changes;  the  reason  for  its  remarkable 
electrical  qualities  as  a  high  voltage  insulator. 

Insulators   for   Telephone,    Telegraph,   Light   and   Power 

HEMINGRAY  GLASS  CO. 

Established  1848  Incorporated  1870 

COVINGTON,  KY. 
Factories        -      -      -        MUNCIE,  INDIANA 


Genuine  "Reliance"  Time  Switches 

.The  machine  that  will  stand  the  test 

THIRTY  DAYS  FREE  TRIAL 

Transportation  prepaid 
GREATEST  OFFER  EVER  MADE 

Manufactured  by  the  sole  inventor,  Benj.  F.  Flegel. 

Beware  of  imitations 


Most 

simple, 

accurate, 

lowest 

price 

eight 

day  Time 

Switch. 


Most 
complete 
line. 
All 
turn 
circuits 
both  on 
and  off. 


Cut  shows  open  face.  Also  made  with  solid  iron  door  for 
outdoor  use.  52%  more  business  in  1913  than  1912.  Still 
more  in  1914. 

There  is  a  good  reason, 

Lowest  List,  Greatest  Discounts, 
Strongest  Guarantee 

Write   today   for   from   one   to   ten   on   thirty   days 

FREE    TRIAL.      IT    MEANS    HUNDREDS 

OF   DOLLARS    TO    YOU. 

Reliance  Automatic  Lighting  Co. 

536  College  Avenue  RACINE,  WIS. 


New  Code 


ARE 
NATIONAL  ELECTRIC  NEW  CODE  STANDARD 


Habirshaw 


FOR  ALL 
SERVICE 


Wi 


ire 


ANY 
PRESSURE 


Company 


OFFICES  AND   WORKS: 

YONKERS,  N.  Y. 


25 


Whether  t  h  e 
wire  or  cable 
be  large  or 
small,  for  high 
or  low  tension, 
the  most  dura- 
ble, efficient  and 
permanent  i  n  - 
sulation  known 

KERITE 


KEMTESSCOMPAHY 


OKONITE 

The  STANDARD 

for 

RUBBER  INSULATION 


TRADE  MARK. 
REG.  U.  S.  PATENT  OFFICE 


INSULATE!) 

WIRES  and  CABLES 

are  standard  because  of 
their  unvarying  reliabil- 
ity in  service. 

CANDEE  Pot  Heads 
OKONITE  Tape 
MANSON  Tape 

Sole  Manufacturers 

THE   OKONITE   CO. 

253  Broadway,  New  York 

Willard  L.  Candee,  Pres.  Geo.  T.  Manson,  Gen.  Supt. 

H.  Durant  Cheever,  Treas.  Wm.  H.  Hodgins,  Secretary 


Roebling  Magnet  Wire 

is  carefully  drawn  and  annealed  to  pro- 
duce a  soft  wire  with  a  minimum  varia-    , 
tion   in   gauge,   and   is    covered   with  •  a 
smooth  and  uniform  insulation. 

The  best  metals  obtainable  and  an  ex- 
perience of  many  years  in  wire  manu- 
facture are  combined  in  the  production 
of  this  and  other  Roebling  wires  which 
include  rubber  covered  wire,  weather- 
proof wire,  lamp  cord  and  all  other 
wires  used  for  electrical  purposes. 

John  A.  Roebling's  Sons'  Co. 

TRENTON,  N.  J. 

Agencies  and  Branches 

New  York  Chicago  Cleveland  Philadelphia 

Pittsburgh          Atlanta  Seattle  Los  Angeles 

San  Francisco     Portland,  Ore. 


JlllllllllHIWHIIItllHIIillllllllllltllffllillilllllltlllliltlllllllllllllHIfllHIill 


INDIANA  RUBBER  AND 
INSULATED    WIRE    CO. 

Paranite  Rubber  Covered  Wires 
and  Cables 

IF  us  PARANITE  ITSRIGHT 

More   Than  Code  Requires 


Underground,  Aerial,  Submarine 

and  inside  use 

Telephone,  Telegraph  and 

Fire  Alarm  Cables 

FACTORY  AND  GENERAL  OFFICES 
JONESBORO,   IND. 

Chicago  Office,  210  So.  Desplaines  St 

Chicago,  Illinois. 

Eastern  Representatives,  THOMAS  &  BETTS  CO. 
105   Hudson  St.,  New  York 


A  Good  Brand 

NATIONAL  CODE  STANDARD 


Reg.  U.  S.  Patent  Office 


of  Electrical  Wires 
and  Cables 

There  are  none  better 

Weatherproof — Slow-Burning  Weatherproof, 
either  black  inside  or  outside — Slow-Burning 
(Old  Underwriters),  Magnet  Wires,  all  sizes 
—Annunciator,  Office,  Enamel,  Signal  Wires 
—Telephone  and  Telegraph  Wires — Rubber- 
Covered  Wires — Bare  Copper  Wires  and 
Strands — Moving  Picture  Machine  Cable — 
Border  Light  Cable — Elevator  Lighting  and 
Signal  Cables.  Quick  shipments,  reasonable 
prices. 

Chicago  Insulated  Wire  &  Mfg.  Co. 

CHICAGO,  ILL. 
ESTABLISHED  1885 


THE  PURPOSE  of 

THE  ELECTRIC 
CABLE   COMPANY 

IS 


First: — To  produce  Rubber  Insulated  wire  and  cables 
of  a  quality  superior  to  that  which  it  is  pos- 
sible to  obtain  from  any  other  manufacturer. 

Second: — To  make  these  products  with  such  efficiency 
and  economy  as  to  permit  of  their  sale  at  a 
price  no  higher  than  it  is  necessary  to  pay 
for  inferior  material. 

Third: — To   prove  our  appreciation   of  our  customers' 
confidence  by  a  conduct  of  business  relations 
which    shall   always   be    courteous,   fair    and 
honest. 
We  solicit  your  inquiries  and  orders  for 


"INVINCIBLE"  "ENGINEERS" 

New   Code   Standard.  High  Grade.  Pure  Para. 

LEAD  ENCASED  CABLES 
For    any    service    and    every    voltage 

THE  ELECTRIC   CABLE  CO. 

17  Battery  Place,  New  York 

Bridgeport  Philadelphia  Chicago 

Boston  Cleveland  San  Francisco 

Works: — Bridgeport,  Conn. 


An  Unchanged  Standard 

The  recent  changes  in  the  rules  established  by 
the  Underwriters  Laboratories  specifying  more 
severe  tests  for  rubber  insulated  wire  will  neces- 
sitate putting  a  better  grade  of  rubber  into  some 
code  wires. 

"Sterling"  N.  E.  C.  Rubber  Insulated  Wire 

required  no  change  in  its  manufacture  to  meet  in  every 
respect  the  new  requirements.  "Sterling"  has  always 
kept  well  in  advance  of  Underwriters'  requirements 
because  it  is  made  to  meet  a  separate  and  independent 
standard  based  on  maximum  quality  and  durability  at 
a  reasonable  and  economical  price. 

When  buying v  N.  E.   C.  wire  look  for  the   Standard 
marking : 
One  green  thread  or  strand  woven  into  the  braid, 

which  is  our  registered  trademark. 

ll'riie    our   nearest   office   for   "Sterling''    booklet. 

Standard    Underground    Cable    Co. 
Pittsburgh,  Pa, 

New  York  Philadelphia  Chicago 

Hoston  San  Francisco  St.  Louis 

Manufacturers    of    Electric    Wires    and    Cables    of    all 
kinds,    all    sizes,    for    all    services,    also    Cable 
Accessories   of  all ,  kinds. 

For    Canada:     Standard    Underground    Cable    Co.    of 
Canada,    Limited,    Hamilton,    Ont. 


33 


* 


Rubber  Covered 


Lamp  Cords 


Automobile  Cable 


Show  Window  Cords        :         Telephone  Wire 


Lowell  Insulated  Wire   Co 


LOWELL,  MASS. 


AMERICAN  ELECTRICAL  WORKS 


PHILLIPSDALE,  R.  I. 


"National  Electrical  Code  Standard" 

Americanite  Rubber  Covered  Wire 
Incandescent  Lamp  Cord 


Weatherproof  Line  Wire 

Slow  Burning  Wire 
Railway  Feeder  and  Trolley  Wire 
Galvanized  Iron  Wire  and  Strand 


NEW  YORK,  165  Broadway      CHICAGO,  112  West  Adams  St. 
BOSTON,  176  Federal  St.          CINCINNATI,.  Traction  Bldg. 
Montreal,  Canada 


Rome  Wire  Company 

ROME,  N.  Y. 


U  fctome-Wice 


Our  Specialties 

Rubber  Covered 
Code  Wire 

Lamp  Cord 
Telephone  Wire 


ROUND-SQUARE-FLAT 
MAGNET  WIRE 


YOU  GET  OUR  PERSONAL  ATTENTION 
ON  ALL  ORDERS 


»7 


ATLANTIC 

WIRES      AND      CABLES 
RUBBER   INSULATED 


NATIONAL 
ELECTRICAL 
CODE 
STANDARD 


[  Extra  High  Grade 


Three  brands  that 
mark  the  maximum 
of  quality  and  ser- 
vice in  their  re- 
spective grades  of 
insulated  wire. 


WRITE   FOR    OUR    PRICE    LIST 

~.       ,    ,1  AND  DISCOUNTS 

Commercial  Code  ]  ' 

ATLANTIC 

INSULATED  WIRE  &  CABLE  CO. 

Sales     Office:    125     Cedar     Street,     New   York 
Factory:  Stamford,  Ct. 


TRADE 


MARK 


Nat'l  Electrical  Code  Standard. 


Quality  is  indicated  and  measured  by  voltage 
tests.     Long  life  and  Superior  Electrical 
Qualities  are  combined  in  our  product. 


Size                       Underwriters 
r»   c   p                             Voltage 

Simcore 
Voltage 
Tests 

14  to  8  inc.                       1500 

2000 

6  to  2    "                         2000 

3000 

1  to  4-0  " 

2500 

5000 

225,000  to  500,000 

3000 

6000 

525,000  and  larger 

.3500 

7000 

SIMPLEX  IRE  &CABLE  (9 

MANUFACTURERS 

201  DEVONSHIRE  ST..    BOSTON 

CHICAGO          SAN  FRANCISCO 


"PHONO -ELECTRIC" 

The  Dependable  Trolley  Wire 


It's  toughness  that  counts  in  an  overhead  wire,  Tough- 
ness not  implied  either  by  tensile  strength  or  elasticity,  but 
a  power  to  resist  bending,  kinking,  wrenching,  sudden 
blows  or  slow  distortions  without  giving  way. 

The  Demand  for  better  cars,  better  roadbeds  and  faster 
schedules  is  yan  indirect  demand  for  better  overhead  wires. 
"Phono-Electric"  is  tough;  and  is  a  wire  that  will  give 
LONG  SERVICE  LIFE. 

You  want  a  money-saving  wire — specify  "Phono-Electric." 
It's  tough. 


Bridgeport  Brass  Company 


Bridgeport 


Connecticut 


Catalogue  Mailed  Free 


All  conductors  carefully^tested] 

N.   I.   R. 

HIGH  GRADE 

Rubber  Covered  Wires  and 
Cables 

FOR  EVERY  SERVICE 

Electric    Light,    Power,    Railway 

Telephone  and  Signal 

NATIONAL  BRAND 

Weatherproof   and  Slow  Burning 
WIRES  AND  CABLES 

National  Electrical  Code  Standard 
NATIONAL  INDIA  RUBBER  COMPANY 

Executive   Office  and  Factory 
BRISTOL,  R.  I.,  U   S,  A. 

General  Sales  Office,  30   Church    Street,    NEW   YORK 

Chicago  San  Francisco 

Clinton  and  Van  Buren  Sts.  579  Howard  Street 

Boston,   201  Devonshire  Street 
41 


Wires  and  Cables 

BARE  COPPER  WIRE 

for  Power  Transmission,  Telephone 
and  Trolley  Lines 

FLAT  COPPER  WIRE 

for  Armature  and  Field  Coils 

ALLOYED  TROLLEY  WIRE 

for  Extra  High  Tensile  Strength  Purposes 

GERMAN  SILVER  WIRE 

for  Resistance  Purposes 

INSULATED    WIRE 

"K.K."  Weather-proof  Line  Wire 

Slow  Burning  Weather-proof  Wire 

Magnet,  Office  and  Annunciator  Wire 

BARE  TRANSMISSION  CABLE 

WEATHER-PROOF 
STRANDED  CABLE 

Prices  Quoted  Upon  Application. 

The  American  Brass  Co. 

ANSONIA  BRASS  &  COPPER  BRANCH 
Ansonia,  Conn. 

BENEDICT  &  BURNHAM  BRANCH 
Waterbury,  Conn. 


American 
IkWireCo 


AM 

RUBBER 


RE 

|®  WIRE 


THE    QUALITY   of    Americore   Wire   is 
such  as  to  make  it  an  absolute  standard 
for  interior  wiring  and  to  give  the  best  pos- 
sible fire  protection. 

Eve4*y  foot  is  carefully  inspected  by  us  in  the 
various  stages  of  manufacture,  and  when  com- 
pleted, is  finally  inspected  by  an  authorized 
representative  of  the  National  Board  of  Fire 
Underwriters. 

We  are  prepared  to  furnish  this  wire 
in  all  sizes  of  conductors,  both  solid 
and  flexible,  from  warehouses  con- 
veniently located  for  quick  delivery 
to  all  parts  of  the  Country. 

American  Steel  &  Wire  Company 


Chicago, 

New  York, 

Worcester, 

Boston, 

Pittsburgh, 

Cincinnati 

Buffalo,     . 


SALES  OFFICES 

72  W.  Adams  St.    Cleveland,     .     . 
30  Church  St.     Detroit,     .     .     . 


.     Western  Reserve  Building 
.     .     .     Foot  of  First  Street 

94  Grove  St.     Oklahoma  City,  State  National  Bank  Building 
120  Franklin  St.     St.   Louis,      .     .     3rd  National  Bank  Building 
FrickBldg.     Denver,     ...     1st  National  Bank  Building 
Union  Trust  Bldg.     St.  Paul-Minneapolis,  Pioneer  Bldg.,  St.  Paul 
337  Washington  St.     Salt  Lake  City,     .     .     Walker    Bank    Building 
United  States  Steel  Products  Company 

Export  Department,   New  York 30    Church     Street 

Pacific  Coast  Dep't,  San  Francisco Rialto     Building 

Portland Sixth    and    Alder   Streets 

Seattle 4th   Ave.  South  and   Conn.  Street 

Los  Angeles Jackson   and   Central   Avenues 


48 


Economy  and  Reliability 


M  &  M  Shallowest  Switch 
1  7/  16"  deep 


M  &  M  Sectional  Wall 

Box  Equipped  with  Loom 

Clamps  2",  2  1/2"  or  3" 

deep 


Catalog  and  Discount  Sheet  on  request 

MachenK  Mayer  Electrical  Mfg.  Co. 


PHILADELPHIA,  PA. 


"Diamond  H"  Switches 

AND  FLUSH  RECEPTACLES 


PUSH  BUTTON  SWITCHES 

ROTARY  FLUSH  SWITCHES 

Rotary  Surface  Switches 

Remote   Control  Switches 


HART  MFG.  CO.,  Hartford,  Conn: 

New  York       Boston       Chicago       Pittsburgh       Denver       Toronto 


REFLECTOLYTE 


The  Unit  of  Quality  and 
Efficiency 


Type  P.  F. 

Porcelain  Enamel  upper  reflector.  Will 
not  crack,  check  or  peel  off.  Made  in 
three  sizes,  16,  20  and  24  inch.  Plain 
and  ornamental,  with  one  or  three  chains. 

A  reflector  with  the  qualities  of  Opal 
Glass  and  the  strength  of  steel. 

Write  for  Catalog  No.  26. 

FRANK  ADAM  ELECTRIC  CO 

St  Louis,  Mo.,  U.  S.  A. 


4ft 


"MEGGER" 

TESTING  SETS 


For  the  use  of  Fire  Underwriters,  Government 
Inspectors,  Consulting  Engineers  and  Electrical 
Contractors  we  have  developed  a  new  Megger 
Testing  Set,  that  can  be  supplied  at  moderate  cost. 

The  range  of  measurement  is  up  to  5  megohms, 
and  the  generator  develops  125  volts  D.  C. 

To  any  one  who  mentions  "Standard  Wiring" 
when  placing  order,  we  will  supply  one  of  these 
sets  at  special  price  of  $120.00  net,  f.  o.  b.  Phila- 
delphia, during  1915. 

For  rapid  and  accurate  tests  of  insulation  resist- 
ance, the  "Megger-method"  is  far  better  than  any 
other  way.  Approved  and  used  by  the  U.  S. 
Government. 

See  text  page  51  for  description  of  the  apparatus. 

James  G.  Biddle 

Electrical  Measuring  Instruments 

1211-13  Arch  St.  Philadelphia 


The  New 


Miniature    Precision   Instruments 

for  Direct  Current 


MODEL  »280 
""(Portable)" 


They  mark  the  highest 
development  in  very 
small  Indicating  In- 
struments, conforming 
in  every  way  to  the 
exacting  W  e  s  t  o  n 
standard. 


PORTABLE 

Volt-Meters,     Millivoltmeters,     Volt-Ammeters,     Ammeters,     Mil- 
Ammeters 

are  supplied  in  single,  double  and  triple  ranges,  the  Triple 
Range  Volt-Ammeter  comprising  six  instruments  in  one.  This 
group  also  includes  BATTERY  TESTERS. 

SWITCHBOARD 

Volt-Meters,  Volt-Ammeters,  Ammeters,  Mil-Ammeters 

This  new  line  of  instruments  represents  the  finest  develop- 
ment of  small  size  pivoted  moving  coil,  permanent  magnet 
type  of  instruments. 

They  embody  characteristics  which  have  made  the  well-known 
Weston  Standard  famous  throughout  the  world.  They  are 
accurate,  dead  beat  and  extremely  sensitive. 
They  may  be  left  continuously  in  circuit  at  full  load  and 
are  shielded  against  external  electrical  and  magnetic  influ- 
ences. 

They    are    substantially    constructed    and    have    the    longest 
scale   ever   provided  in   instruments   of   similar  size. 
The    prices    are    surprisingly    low    for    instruments    of    such 
quality. 

The  several  models  and  ranees  offer  a  selection  from  over 
300  different  combinations.  They  are  listed  in  BULLETIN 
No.  8,  WHICH  WILL  BE  MAILED  UPON  REQUEST. 

Weston  Electrical  Instrument  Co.,  Newark,  N.  J. 


New  York  St.  Louis  Detroit 

Chicago  Denver  Cleveland 

Philadelphia  San  Francisco  Buffalo 
Boston  Atlanta 


Richmond          Vancouver 
Toronto  Winnipeg 

Montreal  Berlin 

London 


" 


Circle  T 


" 


Trumbull  Switches 


Type    "A" 

30-5,000  amp. 

All  styles 


Type    "C" 
30-200   amp. 

Front  connections 
Plain  finish 


Type   "C" 


Large  Sized  Switches  a  Specialty 

Panel  Boards,  Switch  Boards  and  Cabinets 

Comb  Switches,  Panel  Cutouts,  Plug  Cutouts,  Slate  Base 
and  Porcelain  Fuse  Blocks,  Rosettes,  Iron  Service  Boxes, 
Ironclad  Switches,  Battery  Switches,  Flush  Receptacles, 
Panel  Parts,  Wire  Connectors,  Attachment  Plugs,  Mould- 
ing Branch  Blocks,  Moulding  Receptacles,  Snap  Switches, 
Push  Switches,  Insulating  Joints,  Armored  Cable,  and 
Conduit,  etc.,  etc.,  etc. 

Be  sure  to  get  our  1915  catalogue,  No.  10. 

The  Trumbull  Electric  Mfg.  Co. 

PLAINVILLE,  CONN. 

NEW  YORK,  114-118  Liberty  St.  BOSTON,  76-78  Pearl  St. 

PHILA.,   138  No.   10th  St.  SAN  FRAN.,  84-88  Second  St. 

CHICAGO,  15  So.  Desplaines  St. 


PIGNOLET   INSTRUMENTS 

ACCURATE 

COMPACT 

INEXPENSIVE 

Voltmeters,  Ammeters   and 
Volt-Ammeters 

PORTABLE    AND    SWITCHBOARD    TYPES 

FOR   ALTERNATING   AND   DIRECT 

CURRENT. 


OUR    NEW    MODEL    P. 

The  handiest  Direct  and  Alternating  Current  Portable 
Meter  made;  6"  long,  5"  wide,  3"  deep;  weight  less  than 
3  Ibs. 

We  also  make  several  styles  of  Pocket  Meters;  4^' 
long,  3%"  wide,  i%"  deep,  with  an  extra  long  scale  per- 
mitting close  readings. 

Send  for  complete  Catalog  and  Directions  for  Testing. 


L.  M.  PIGNOLET 

Cor.  Cortlandt  and  Washington  Streets 
NEW  YORK,  N.  Y. 


50 


I.    U.    Volt    Ammeter 


A  distinguishing,  we  might  almost  say  exclusive 
feature  of  the 

HOYT  Une  of 
Ammeters  •*>  Voltmeters 

is  their  extreme  flexibility  adapting  them  to  prac- 
tically every  use  required  in  modern  practice. 

Ask  for  Bulletin  SW 

Hoyt  Electrical  Instrument  Works 

PENACOOK,  N.  H. 


6"  Type 


Pocket    Ammeter 


DOSSERT  CONNECTORS 


2-Way   Type   A   Showing:  Details. 

Dossert  Connectors  eliminate  entirely  the  use  of  solder  in  making 
electrical  connections  and  splices,  and  are  approved  for  use  without 
solder  by  the  National  Board  of  Fire  Underwriters  for  all  classes 
of  wiring. 

By  their  use  much  labor  is  saved  and  splices  obtained  that  will 
withstand  any  overload.  Many  careful  tests  show  that  a  splice 
made  l>y  means  of  a  Dosserfc  Connector  will  not  heat  as  much  as 
the  cable  which  it  connects  when  the  cable  is  heavily  overloaded. 

Type  A  Connectors  are  for  use  on  cables,  stranded,  or  solid 
wires,  rods  and  tubing.  They  are  simple  and  effective,  and  by 
their  use  splices  can  be  quickly  made  in  conductors  of  any  size. 
Type  A  Connectors,  however,  should  not  be  used  on  a  cable  that 
is  to  be  subjected  to  heavy  tensile  strains. 


Part  Cross-sectional  View  of  Type  B  2-Way 

Type  B  Connectors  are  for  use  on 
stranded  wires  or  cables  only,  and  are 
designed  to  make  a  joint  which  will 
withstand  heavy  tensile  strains.  They 
are  not  made  for  wires  smaller  than 
No.  0. 

The  Cable  Tap  is  used  to  connect 
a  branch  wire,  rod,  or  bleeder,  to  a  main 
wire,  rod  or  feeder.  It  does  not  splice  the 
main,  but  simply  clamps  on  to  it.  Branch 
wire  is  connected  to  cable  tap  by  means  of 
a  nut  and  sleeve  as  shown  in  Type  A  cut. 

With  Dossert  devices  any  combination  9f 
different  sizes  of  cables,  stranded  and  solid 
wires,  rods  and  tubing  can  be  connected  to- 
gether. The  cable  tap  will  tap  from  any  size 
main  to  any  size  branch.  Terminal  and 
switchboard  lugs,  front  or  back  connected; 
angle  and  swivel  lugs.  Insulated  connectors; 
two-ways,  three-ways,  equalizers,  cable  an- 
chors, reducers,  elbows,  Y's,  service  box  lugs 


Cable  Tap 


and    plugs,    grounding    devices    and    stud    connectors    for    threaded 
rods   and   flat   strips   or   locks. 

Send  for  Tenth  Year  Catalogue. 

Dossert  &  Company 

H.  B.  LOGAN,  President 

242  West  41st  Street  New  York,  N.  Y. 


"Griptite"  and  "Flexclamp" 

GROUND  CONNECTION  CLAMPS 


For  Rigid  and  Flexibh 

Conduit 

National  Electrical 
Code  Standard 


Made  of  one  piece  of 
copper  insuring  perfect 
and  permanent  contact. 

Made  for  all  Standard 
sizes  of  rigid  and  flex- 
ible metallic  conduit. 


Patented 


Pat.  Pending 


"NECO"  Wire  Gauge 


Our  IMPROVED  "NECO" 
POCKET  WIRE  GAUGE,  for  meas- 
uring wire  from  No.  18  to  No.  000 
B.  &  S.  Gauge.  On  the  front  is  also 
given  the  carrying  capacity  of  cop- 
per wire  in  amperes  and  on  the  re- 
verse side  the  approx.  decimal 
equivalent  of  the  various  size  wires. 

Mailed  to  any  address  in  the 
United  States  or  Canada  upon  re- 
ceipt of  60  cents  in  cash  or  money 
order. 

Manufactured    by 


Novelty  Electric  Company 

Wholesale   Electrical   Supplies 

50-52-54  North  4th  St.,  PHILADELPHIA 

Agents  for  Okonite  Wires  and  Cables 

Holtzer  Cabot  Motors 


53 


CONDUIT  WORK 


AT  ODERN  construction  makes  essen- 
1VJ-  tial  the  use  of  an  armor  or 
metal  protection  to  electric  wires; 
mechanical  injury  during  construction 
or  after  completion  of  the  work  causes 
such  annoyance,  expense  and  damage, 
that  the  first  cost  of  a  conduit  system 
over  knob  and  tube  work,  exposed  wir- 
ing, molding  or  non-metallic  tubing 
construction  is  now  considered  of  no 
consequence  when  safety  by  metallic 
conduit  protection  is  secured. 

FIRST  IN  PROTECTIVE  QUALITIES  IS 
"Galvaduct"  ] 

"Loricated"  }-  Rigid  Conduits 

"S.-A.C.Co.  Special" 
"Sterling"  Flexible  Steel  Conduit 

Metallic  Flexible 

"Sterling"  Steel  Armored  Conductor 

(All  Patented) 

THEY  ARE  THE  BEST 

Literature  and  samples  upon  request 

Safety- Armorite 

Conduit  Company 

PITTSBURGH,  PA. 
Rigid  Conduit  Agent  NATIONAL  TUBE  CO. 

54 


NON-METALLIC   FLEXIBLE   CONDUIT 

An  Excellent  Tubing 

^V^ijf^  §7  MAfrK 

is    scientifically    constructed 

<I  The  inner  tube  is  of  closely  woven  smooth 
canvas. 

<I  The  frame-work  consists  of  spirally  wound 
resilient  fiore. 

<I  Highest  quality  of  material  and  insulating 
compounds. 

<I  No  irregularities — no  obstructions. 
<I  Tough  and  strong,  yet  flexible. 

<I  Smooth  and  firm  inside  surface — cuts  clean 
and  fishes  free. 

<I  The  size  of  the  interior  diameter  remains 
equal  and  circular  throughout  the  runs,  and 
there  is  no  splitting  or  pulling  apart. 


The  American 
Conduit  Manufacturing  Co. 

Pittsburgh,  Pa. 


65 


"Order  by  Name" 

ALPHADUCT 


Meets  with  in- 
stant approval  of 
Architects,  Engi- 
neers, Contrac- 
tors and  Inspec- 
tors. 

Send  for  cata- 
logue. 


Combines  per- 
fect flexibility 
of  conduit  with 
strength  and  so- 
lidity of  wall. 

Easiest  to  "Fish." 

Try  it  and  prove 
it. 


THE  HIGHEST  ACHIEVEMENT  IN  THE  ART 
OF    INTERIOR    CONDUIT    CONSTRUCTION 


Inner      lining      of 
heavy   canvas. 


Water-proof   coat- 
ing. 

Hard  fibre  cord. 


All  intersects  filled 

with     special 

compound. 


Outer  jacket. 


Outer    coating 
protection  against 
dampness  and 
abrasion. 


Finished  Conduit 


ALPHADUCT  CO.  136 


N., 


56 


"XDUCT"  GALVANIZED  CONDUIT 

Easy-Bending    Spellerized    Steel    Tube,    Doubly 
Protected  by  Copper-Plating  and  Zinc- 
Coating.    Clean  Threads    Smooth 
Enameled  Interior. 


"ELECT80DUCT" 

ENAMELED  CONDUIT 

Easy-Bending  Spellerized  Steel  Tube,  Protected 

by  Coatings  of  Special  Enamel. 

Smooth  Interior. 


"LOOMFLEX"  FLEXIBLE  CONDUIT 

Seamless     Interwoven     Canvaslike     Soapstoned 

Interior  covered  by  a  Light  Cotton  Braid. 

Clean  to  Handle.     Easy  to  Cut 

and  Fish. 


"CIRCULAR  LOOM' 

FLEXIBLE  CONDUIT 

Fibre    Spiral    Soapstoned    Interior,    covered    by 

Insulating  Tape  and  a  Heavy  Woven 

Cotton  Jacket. 

American  Circular  Loom  Co. 

Main  Office:  90  West  Street,  New  York 

SELLING    AGENTS  • 

New    York:    R.    B.    Corey    Co.,    39    Cortlandt 
Street. 

Chicago:    Geo.    C.    Richards,   629   W.    Jackson 
Blvd. 

San    Francisco:      L.    E.    Sperry,    629    Howard 
Street. 

Seattle:    H.    G.    Behneman,    Inc.,    316    James 
Street. 

Los    Anereles :     R.  .  B.     Clapp,    600    San    Fer- 
nando   Bldg. 


DURADUCT 

Reg,U.5.Pai.Off. 


Duraduct  is  a  non-metallic  flexible  conduit.  It  is 
an  indestructible,  non-collapsible,  inseparable 
woven  wall.  This  single  wall  is  made  by  inter- 
weaving the  hard  twisted  insulating  paper  cord 
with  cotton,  the  fabric  wall  is  then  treated  with 
both  waterproofing  and  fireproofmg  compounds. 


A  single  wall  means  that  there  is  nothing  to 
blister  or  pull  apart  and  if  the  conduit  is  crushed 
it  is  rounded  into  shape  by  the  fingers.  The 
interior  surface  being  corrugated  fishing  is  re- 
duced 75%. 

All  2/8  inch  and  1/4  inch  sizes  are  packed  in 
corrugated  boxes  (1000  ft.).  Duraduct  comes 
to  you  every  inch  good,  clean  and  usable.  A  big 
saving.  All  good  jobbers  sell  Duraduct. 

Tubular  Woven  Fabric  Co. 

Mfrs.,  Pawtucket,  R.  I. 
A.  HALL  BERRY,  General  Sales  Agent 

97  Warren  St.,  New  York     309  S.  Desplaines  St.,  Chicago 


"BUCKEYE"  Conduit 

Enameled  and  Galvanized 


The  standard  by  which  other  conduits 
are  judged,  approved  by  the  leading  arch- 
itects, engineers,  railroads  and  public 
service  commissions.  Highest  quality, 
prompt  shipment,  and  prices  that  'are 
right. 


TheWesteroConduitCo, 

Youn^stown,  Ohio. 

.Subsidiary  to 

The  Youn^stown  5heet  &  Tube  Co, 


"NATIONAL"  PRODUCTS 

SHERARDUCT 

The  rigid  steel  conduit  with  both  interior 
and  exterior  surfaces  protected  with  a 
non-corrosive  zinc-steel  alloy. 

ECONOMY 

Enameled  Rigid  Steel  Conduit 

FLEXTUBE 

The  Seamless  Non-Metallic  Flexihle  Con- 
duit with  the  inseparable  "roller  hearing" 
interior. 

FLEXSTEEL 

Flat  Surfaced  Flexible  Metallic  Conduit, 
Armored  Conductors,  Armored  Lamp 
Cord,  and  a  complete  line  of  improved 
fittings. 

"NATIONAL" 
Metal  Molding  and  Fittings 
Locknuts  and  Bushings 
Sherardized  Stamped  Steel  Fixture  Studs 
Outlet  Boxes  and  Covers 

Write  for  catalogue,  samples  or 
other  desired  information. 

NATIONAL  METAL  MOLDING  COMPANY 

PITTSBURGH 

Boston  New  York  Chicago 

Atlanta  Denver  San   Francisco 

Los  Angeles  Portland  Seattle 

Buffalo  Detroit 


Buckeye  Mazda 


The   Most   Efficient    Lamps 
Manufactured  Today 

Bear  the  trade-mark  "Mazda."  Made  in  all  sizes  from 
10  watt — 1.3  w.p.c.  to  1,000  watt — .55  w.p.c. 

Secure  maximum  efficiency  by  using  "Buckeye 
Mazda  Lamps"  in  every  socket.  Special  lamps  for 
special  purposes. 

Our  Engineering  Dept.  is  at  your  services  and  will 
be  glad  to  assist  you  in  any  lighting  problems  you 
may  have. 

/.     The     .*. 
Buckeye  Electric  Division 

National  Lamp  Works  of  General  Electric  Co. 
CLEVELAND 

CHICAGO  PITTSBURGH  BOSTON 


61 


Safety  from  Lightning- 

Your  Price 


Small  Air  Gaps  will  Give 
You    Protection. 


Low  Series  Resistance 
will  Eliminate  Surges, 
Low  Voltages,  Winking 
Lights  on  Your  Circuits. 


The  Circuit  Breaker  will 
Eliminate  Grounds  and 
Short-Circuits  on  Your 
Lines. 


The  circuit  breaker  used  in  com- 
bination   with    a    small    air    gap 
}         and    a   low   series    resistance    has 
given 

Carton-Daniels  Lightning  Arresters 

their    well    known    characteristics    of    efficiency    and    durability. 

The  air  gaps  mean  protection  to  your  electrical  apparatus, 
because  they  arc  over  and  discharge  potentials  but  slightly 
higher  than  normal. 

The  low  series  resistance  will  eliminate  surges,  winking  lights 
and  other  voltage  disturbances  on  your  circuits,  because  it  limits 
the  flow  of  line  current,  following  the  lightning  discharge  to 
ground  to  a  moderate  value — about  10  amperes. 

The  circuit  breaker  will  eliminate  grounds  and  short-circuits 
on  your  lines,  because  it  always  positively  and  unfailingly  cuts 
off  this  flow  of  line  current  to  ground. 

You  can  get  complete  lightning  protection  only  from  an  ar- 
rester combining  these  three  essential  functions. 

An  installation  of  Carton-Daniels  is  your  only  price  for 
Safety.  Write  for  catalog. 

Electric  Service  Supplies  Co. 

Railway  Material  and  Electrical  Supplies 

PHILADELPHIA,   17th   and   Cambria   Sts. 
NEW  YORK,  Hudson  Terminal. 
CHICAGO,    417    So,    Dearborn    St. 


62 


The  Cook  Wedge  Split  Insulator 

One  er  Two  GROOVE  for  10, 12, 14  Wire 
Makes  Standard  Wiring  Easy 

Made  of  the  Best  Hard  White  Porcelain.  No  Burrs  or  Rough 
Edges  to  Cut  Insulation,  but  Firmly  Grips  the  Wire  when 
Screwed  in  Place — The  Cap  Needs  vno  Centering.  Once  Used 
Never  Replaced. 

Trial  Orders  Packed  500  in  a  Box 


Protected  by  U.   S.   Patents. 

Ask  Your  Jobber  or  Write  Us  for 
Samples  and  Prices. 

COOK  POTTERY  CO 

Trenton,  N.  J. 

SOLE  MANUFACTURERS 


63 


BURNLEY 

SOLDERING    PASTE 

Non-Corrosive 
Self-Adhesive 
Free  of  Acids 

Economical 

Patented. 

Especially  adapted  for  all  kinds  of  Electrical 
Work. 

Put  up  in  2-oz.,  4-oz.,  y2->  i-,  5-,  10-  and  so-lb. 
tins.  The  2-oz.  and  4-oz.  sizes  are  packed  3 
doz.  in  cardboard  boxes. 

We  are  always  ready  to  furnish  samples  FREE 
upon  request. 


BURNLEY 

SOLDERING   SALTS 

These  SALTS  are  a  combi- 
nation of  pure  chemicals  so 
proportioned  as  to  give  the 
best  results,  as  a  FLUX,  for 
all  kinds  of  SOLDERING. 

Put  up  in  y2-  and  i-lb.  bot- 
tles, also  y2-  and  i-lb.  fric- 
tion top  cans. 

Ask  for  prices. 


BURNLEY  PASTE  AND  SALTS 

Manufactured  and  put  up  by 

THE  BURNLEY  BATTERY  &  MFG.  CO 

Chas.  E.  Chapin  Co.  North  East,  Pa., 

201  Fulton  St.,  U.  S.  A. 

New  York  City,  Agent. 


Lux  Lamps  Last  Longest 
THE 

Drawn  Wire  Tungsten 

Nitrogen 
AND 

Concentrated  Filament 


• 


Lamps  made  by 
this  company  are 
strictly  high  grade 
and  suitable  for 
all  purposes  and 
conditions. 


Write  for  Prices. 


LUX  MANUFACTURING  CO 

HOBOKEN,  N.  J. 


65 


The 

Post -Glover  Electric  Co. 

CINCINNATI         :-:         :-:         :-:        OHIO 
Manufacturers  of 

Switch  Boards 

Standard  and  Special  Boards  for  direct  and 
alternating  current. 

Panel  Boards 

For  125,  125  to  250  and  250  volts  for  2  to  2 
wire,  3  to  2  wire  and  3  to  3  wire  systems,  de- 
signed for  open  link  fuses,  N.  E.  C.  S.  enclosed 
fuses  or  plug  fuses,  with  or  without  switches  in 
mains.  Approved  by  Underwriters. 

Cabinets,  Flush  or  Surface 

types,  constructed  of  steel  or  wood  with  or  with- 
out wiring  compartments,  with  wood  or  steel 
trims  and  with  or  without  glass  paneled  doors. 
Approved. 

Knife  Switches 

Type  A — 125,  250  and  600  volts  front  or  back 
connected,  with  Or  without  fuse  connections,  30 
to  5,000  amperes,  latest  designs.  Special  switches. 
Approved  by  Underwriters. 

Write  for  catalogue. 


Perkins  Dead  Front 
Distributing      Panel 


All  connections  and  conductors  are  concealed  and 
separated  from  the  front  of  the  panel  by  a  continuous 
sheet  of  insulating  material.  There  are  no  live  parts 
exposed. 

With  a  quantity  of  these  units  in  stock,  the  con- 
tractor is  ready  to  make  up  lighting  panels  of  any 
size,  thus  avoiding  delays  or  expensive  stock. 

Ease  of  assembling  parts  minimizes  installation  cost. 
Panels  can  be  assembled  for  considerably  less  than 
$1.00  per  circuit. 

•  Perkins  Dead  Front  Panels  may  be  installed  in 
any  standard  steel  or  wood  cabinet  having  a  mini- 
mum depth  of  three  inches. 
Panel  units  can  be  fur- 
nished with  dull  black  cov- 
ers and  black  switch  han- 
dles, or  white  enamel  cov- 
ers and  white  handles. 


An  eight-circuit  Perkins  Dead 
Front  Distributing  Panel  in- 
stalled in  a  gutter  box. 


THE  BRYANT  ELECTRIC  COMPANY 


NEW  YORK 


BRIDGEPORT,  CONN. 
CHICAGO 


SAN  FRANCISCO 


Wakefield  Standard 
Universal  Lighting  Fixtures 

In  Wakefield  fixtures  are  combined  two  characteristics — 
quality  and  substantial  attractiveness  of  design.  In  every 
Wakefield  design  you  get  a  fixture  built  for  service  first, 
then  built  in  a  design  that  will  wear  well;  no  extremes 
that  quickly  come  in.  style  and  as  quickly  go  out  again. 

The  characteristic  of  quality 
is  a  broad  one.  It  means  first, 
good  heavy  gauge  Brass  ma- 
terial throughout.  It  means 
second,  accurate  mechanical 
construction.  It  means  third, 
that  troubles  in  handling  have 
been  anticipated  and  Wake- 
field  Fixtures  made  with  more 
special  features  to  make  them 
easier,  to  wire,  easier  to  put 
together,  easier  to  install, 
easier  to  carry  in  stock,  than 
the  ordinary  lines. 

It      means      service  —  First, 
Last  and  Always.     When  you 
buy    Wakefield    Fixtures    you 
buy  the  experience  of  practical 
people   to   give  you   something 
that  you  can  make  just  a  little 
more  money  on  than  the  aver- 
age and  at  the  same  time  you 
can  give  your  customer  a  sat- 
isfactory article. 
Whether  you  buy  an   attractive  shower  or  an  efficient 
"Mellowlite"  Semi  Indirect  Fixture,  you  get  some  feature 
that  means  more  profit  for  you  in  time  saved,  reputation 
saved  and  fixtures  more  easily  sold. 

Send  for  complete  catalog  of  electric  designs. 

The  F.  W.  Wakefield  Brass  Company 


Vermilion, 


Ohio 


ESSENTIALS 

FOR 

STANDARD     WIRING 

f  Guaranteed  Durability  1 
j£ctlon     I  Reasonable  Price 
lapel  High  Grade 

[  Perfect  Insulation 

ALL  EMBODIED  IN  OUR 

M.  C.  TAPE 

Snlirinrr  f  Perfect  Insulation 

OpllCing  I  perfect  Adhesion 

Compound  j  Per[e<*  s«fcty 

(Pure  Rubber  Tape)      1  PerfeCt   J°mt   WIth°Ut  Heat 
For  mending  Insulation  on  Wire  and  all  High  Tension  Work 

OUR  THREE  SELECTIONS 

"WALPOLE"— "KEPONSEr-"UNION 

MOULDING  VARNISH 

Our  No.  4  is  Approved  by  the  Underwriter 

REASONABLE  IN  PRICE 


If  your  dealer  doesn't  handle  our  goods,  write  us 

• 

Walpole  Tire  &  Rubber  Co. 

WALPOLE,  MASS. 

Pioneers  in   Insulation  Engineering 

Massachusetts  Chemical  Co.'s  Products 


G.  V.  Electric  Trucks 


Give  you  10  or  more  years'  life, 
odorless. 


Are  clean,  silent  and 


Operate  297  days  out  of  the  300.     (Average  statistics.) 

Show  economy  in  tires,  parts,  replacements  and  general 
upkeep  over  a  period  of  years. 

Promote  the  highest  efficiency  in  systematic  trucking, 
transfer  work  and  light  deliveries. 

Make  possible  undreamed-of  economies  in  real  estate 
investment  covered  by  stables  and  wagon  yards. 


Design  standardized  since  1907.  All  parts  of  each  model 
interchangeable.  Many  new  and  exclusive  refinements. 

Over  4,000  in  use,,  many  ten  years  old. 

The  ex-teamster  and  the  simple  Electric  are  a  saving 
over  the  complex  motor  vehicle  and  the  expert  chauffeur- 
machinist. 

The  Electric  has  economic  law  behind  it  and  must  domi- 
nate in  its  field.  "  Show  your  business  acumen  by  getting 
the  right  machine  for  the  right  place. 

Six  models;  1,000  Ibs.  to  5  tons. 

Catalogue  35  on  request.       -  ;    . 

General  Vehicle    Company,  inc. 


General  Office  and  Factory 
Long  Island  City,  N.  Y. 


New  York 


Chicago 


Boston 


Philadelphia 


70 


DRIVER-HARRIS   WIRE   CO. 


RESISTANCE    ALLOYS 


ROUND  OR  AA7TT>  T?   RARE    OR 

FLATTENED     VV  IJVIl/  INSULATED 

"NICHROME" 

For  Electric  Heaters 

"ADVANCE" 

For  Controllers,  Arc  Lamps 

"CLIMAX" 

For  Moving  Picture  Rheostats 

"No.  193  ALLOY" 

For  Heavy  Duty  Rheostats 

"THERLO" 

For  Instruments  and  Shunts 

A  RESISTANCE  WIRE  FOR  EVERY  REQUIREMENT 

Armature  Binding  Wire 

Hercules    (T^g?LD)    Phosphor    Bronze 

Heater  Cords 

Pure  Nickel  and  Nickel  Alloys 
Sheet  Wire  and  Strip 

DRIVER-HARRIS  WIRE  GO. 

Main  Office  and  Works:  HARRISON,  NEW  JERSEY 

Branch:  565  West  Washington  Bldg.,  CHICAGO 


71 


Electrical  Materials 

"Noark"  Enclosed  Fuses;  Fuse,  Service  and  Subway 
Boxes;  Service  Meter  Protective  Devices. 

Frink  and  J-M  Linolite  Systems  of  Electric  Lighting,  for 
Banks,  Churches,  Offices,  Show  Windows  and 
Show  Cases.  Lighting  Fixtures  and  Reflectors. 

Arc  Lamp   Hangers. 

Westinghouse    Tungsten   and    Carbon   Lamps. 

J-M  Trolley  Line  Material,— Cross-Overs,  Rail  Bonds 
and  Tools.  J-M  Mine  Supplies. 

J-M  Electric  Heaters.  J-M  Friction  Tapes  and  Splicing 
Compounds. 

"Moulded   Mica"   Weatherproof  Sockets. 

"Moulded  Mica" — J-P  Bakelite — Electrobestos — and 
Vulcabeston  Insulation. 

J-M  Fibre  Conduit.  J-M  Porcelain  and  Glass  Insula- 
tors. 

J-M   Niagrite    Fireproof    Cable    Insulation. 

J-M   Immovable  Guy  Anchor.      J-M  Insulated  Coupler. 

J-M  Pole  Line  Hardware.  J-M  Detail  Supplies  for  Power 
Work. 

J-M    Ebony  Asbestos   Wood.      J-M  Hard  Fibre. 

J-M  Dry  Batteries;  Battery  Ammeters;  Battery  Connec- 
tors. 

J-M  Indurated  Fibre  Specialties.  J-M  Transmission  Ma- 
terials. 

J-M   Victor  Combination  Meters. 

J-M   Electrotherm  Heating  Pad. 

Write    nearest    Branch  for  Booklet. 


H.  W.  JOHNS-MAN VI LLE  CO. 


Albany 


Baltimore 
Chicago 
Cincinnati 
Cleveland 
Columbus 
Denver 
Detroit 
Galyeston 
Indianapolis 
Kansas    City 
Los    Angeles 
Louisville 
Memphis 
Milwaukee 


Boston 
Minneapolis 
Newark 
New    Orleans 
New   York 
Omaha 
Philadelphia 
Pittsburgh 
Portland 
Salt  Lake  City 
San    Francisco 
Seattle 
St.    Louis 
Toledo 


Buffalo 


2280 


Every  Blown  Fuse  Is  An 
Expense 

Every  fuse  that  blows  under  its  rated  capacity 
is  an  unwarranted  expense. 

Many  do  not  analyze  the  causes  that  add  dol- 
lars to  their  fuse  bills. 

Defective  interior  construction,  weak  joints 
and  imperfect  alignment  of  blades  cost  fuse  con- 
sumers hundreds  of  dollars  a  year. 


Consider  These  Points  In  "D  &  W" 
Construction 

The  links   are   scientifically  designed. 

Every  joint  is  riveted  as  well  as  soldered. 
They  won't  let  go. 

The  blades  are  properly  aligned.  Excessive 
heating  is  eliminated. 

All  metal  parts  are  ample  and  are  securely 
fastened  to  the  tube. 

"D  &  W"  knife  blade  fuses  may  be  refilled  by  the 
factory  at  an  approximate  saving  of  63%. 

They  are  approved  by  the  National  Board  of  Fire 
Underwriters. 

SPECIFY  "D  &  W"  AND  GET  MORE  FUSE  VALUE 


D&W  FUSE  COMPANY 

Providence,  R.  I. 


Whether 
the  Job 

Be  Large  or  Small 

It  will  pay  to  use 

"UNION" 
Fuse  and  Box  Material 


A  Complete  Line  of 

Open  and  Enclosed   Fuses,  Cut-Out  Blocks, 
Fittings,  etc.,  for  All  Voltages. 

All  "Union"  Material  is  made  in  accordance  with  the  re- 
quirements of  the  National  Board  of  Fire  Underwriters. 
"Union"  Fuses,  above  60  amperes,  may  be  reloaded  at  our 
Factory  at  a  large  saving  to  the  user,  and  are  approved. 

Outlet  Boxes  and 
Covers  to  accom- 
modate all  regular 
wiring  devices. 


Switch  Boxes  that  can 
be  easily  taken  apart 
and  rebuilt  into  gangs 
by  the  use  of  spacers. 
The  Standard  Line. 
Pat.  Apr.  2, 1907;  Mar. 
1,  ]910;Feb.  13,  1912. 


Gem  X,  Sectional 
Switch  Box 


No.  106— O  Box  and 
No.  106— D  Cover 


Write  for  Fuse  Catalog  No.  26  and 
Box  Catalog  No.  27. 


CHICAGO  FUSE  MFG.  CO. 


CHICAGO 


NEW  YORK 


"SQUARE   D"    Enclosed   Entrance 
Switches  and  Distributing  Cabinets 

A  line  of  New  Installation  and  Service  Devices  Un- 
equalled in  Excellence  of  Design  and  Finish,  in 
Quality,  in  Safety  of  Operation  and  in  Low  Price. 


"SQUARE  D"  Features 

All  live  parts  enclosed 

Control  outside  "box 

Removable   top   and   bottom   end 
plates 

End   plates   interchangeable 

End   plates    Standard   equipment 

Meter  protective  trim 

Meter   trim   and   end   plates   inter- 
changeable 

Convenient  knockouts 

Ground  wire  lugs 

Exclusive  "locking  off"  device 

Roominess  inside 

Connections   easily  made 

Not  less  than  30  Amp.  capacity 

Made  from  16  Ga.  steel 

Corners   electrically  welded 

Finished  in  lustrous  black  enamel 

Switch  and  cutout  mounted  ready 
to  install 

Satisfactory  operation  assured 

Prevents    accidental    contact    with 
live  parts 

Prevents    tampering    with    service 


No.  5211E.  With  meter 
protective  trim.  Switch  in 
"on"  position,  cabinet 
sealed. 


"ARKLESS"  Fuses  N.E.C.S. 

Only  Guaranteed  Mechanical  Indicator  Made 

All  National  Electrical  Code  Standard 
"ARKLESS"  Fuses  comply  strictly  with 
the  requirements  of  the  National  Board 
of  Fire  Underwriters  and  are  approved 
by  the  Underwriters'  Laboratories  after 
examination  and  test  under  the  provisions 
of  the  National  Electrical  Code.  We 
guarantee  "ARKLESS"  fuses  to  indicate, 
and  will  replace,  free  of  charge,  every 
"ARKLESS"  fuse  that  fails  to  indicate 
when  blown. 

Write  for  Catalog  No.  22  S.  W. 

DETROIT  FUSE&MFG.CO. 

Detroit,  Mich. 


"Shawmut"  Fuses 


Exclusive 
Features 


Black  Tube 
Copper  Ends 

Ampere  Capacity  Stamped  on  Ferrule 
Efficiency  Indicator 


"Shawmut"  Bases 


All  current  carrying  parts  copper. 
Lugs  flush  with  edge  of  slate. 

Clips  have  ample  carrying  capacity 
and  being  in  perfect  alignment 
afford  maximum  contact. 

Condit   Electrical  Mfg.  Co. 

Boston,  Mass. 


W.    S.    Brown   Elec.   Co., 
3   W.    29th    St.,   New   York   City 

F.    V.    L.    Smith, 
1206  Empire   Bldg.,  Atlanta,   Ga. 
Hendrie     &      Bolthoff     Mfg.      & 

Supply    Co.. 
1627    17th    St.,    Denver,    Colo. 


H.    G.    Behneman, 
617    4th    Ave.,    Seattle,    Wash. 


T.    G.    Grier    Co., 
318    W.    Washington    St., 

Chicago,  111. 

Weiss-Bosley    Co., 

1403   Chestnut  St.,  St.  Louis,  Mo. 

Holabird-Reynolds    Co., 

523-525    Mission    St., 

San     Francisco,    Calif. 


"Insure  Against  Loss  of  Lamps" 

You  cannot  always 
prevent  Incandescent 
lamps  from  being  broken, 

but  y°u  can  p.re- 

vent  their  being 
stolen—  and  75%  of  those 
lost  are  stolen. 


The  Socket  that  Locks 
will  prevent  this—  is 

LAMP  INSURANCE 

Sell  it  to  yourself  by  try- 

ing  to  remove  the  lamp, 

without  the  use  of  the   Master 


key  ~and  then  specify    5*™^i<>H.  on    your 
next  order. 

Sold  by  jobbers  everywhere 

Descriptive  booklet  and  sample  gladly 
supplied  on  request. 

PASS  &  SEYMOUR,   Inc., 

Solvay,  N.  Y.,  U.  S.  A. 

New  York  San  Francisco  Chicago 

178  Fulton  St.         Rialto  Bldg.         700  W.  Jackson  Blvd. 


78 


The  MonitorSystem 


START 


SAFETY 


The  Original 
"Just  Press 
a  Button" 

controller 


'Just  Press  a  Button' 

Affords  simple  but  complete  control 
of  every  movement  required  of  any 
motor-driven  machine. 
Prevents  accidents,  save  motor,  man 
and  machine. 

There  is  a  type  of  Monitor  Control- 
ler  for    every    need — Either    alter- 
nating or  direct  current. 
Ask  particularly  for  details  of  our 
"Safety  First"  Station. 

MonitorControllerCompany 

III  South  Gay  Street,  Baltimore 


New  York,  30  Church  St. 
Philadelphia,  1533  Chestnut  St. 


Boston,  77  Franklin  St. 
Chicago,  Old  Colony  Bid*. 


EVERY  ONE  OF  THE  30,000  READERS  OF 

"  STANDARD  WIRING "  SHOULD  HAVE 

THIS  NEW  BOOK 

"A    Complete    Reference 
Library   in    Itself" 


AMERICAN 
HANDBOOK 

FOR 

ELECTRICAL 
*t   ENGINEERS 


EDITED  BY 

DR.  HAROLD  FENDER, 
Professor  of  Electrical  En- 
gineering, University  of 
Pennsylvania,  and  26  Asso- 
ciate Editors,  each  an 
authority  in  his  field. 

A  Really  Practical  Handbook 

In  this  book  everything  has  been  done  to  make 
it  as  useful  as  possible.  For  this  reason,  it  has 
been  necessary  to  break  away  from  the  usual 
handbook  construction. 

As  an  example  it  is  the  first  handbook  to  have 
an  alphabetical  arrangement,  making  it  easy  to 
find  any  subject  desired.  Then  too,  the  Practical 
Data  is  grouped  separately  from  discussions  of 
Theory,  a  feature  that  should  appeal  to  all  busy 
men. 

These  features  and  many  others  make  this  a 
book  that  you  should  not  be  without. 

2023  Pages  Thoroughly  Illustrated 

Morocco  $5  Postpaid          Size  41/4x7 

Send  in  your  order  to-day — you  have  the  privilege  of 
returning  the  book  within  10  days  and  your  money  re- 
funded. 

JOHN  WILEY  &  SON,  Inc. 

432   FOURTH  AVE.  NEW  YORK   CITY 


NOKORODE  SOLDERING  PASTE 

Made  with  more  care  than  nine-tenths 
of  the  druggists  compound  a  doctor's 
prescription. 

Every  particle  contains  all  the  ele- 
ments of  the  flux. 

Used  exclusively  by 

U  S'  Gov>t  90%  of  the  Elec- 

on  the  //O  it      trical  Trade  of 

telephone  New  York  and 

X>vT*«  **.W|>t/irroi«  &>.,yy        \      TVT  T~*  11  1 

circuits  of  §/  New  England  and 

for  eleven 
the  Panama        |v_  rs  b    The 

Canal  W  N.E.Tel. &Tel. Co. 


PRICE  LIST 

2  oz.  Cans,  less  than  case  lots      -         -     $0.25  each. 
2  oz.       "       3  dozen  (one  case)  2.00  doz. 

1  Ib.       "1-2      "        (one  case)      -         -       1.00  Ib. 

10  "         » 1.00  Ib. 

25  Ib.  and  50  Ib.  Cans    -  .90  Ib. 

DISCOUNT  IN  CASE  LOTS  50  PER  CENT. 
Discount  in  less  than  Case  Lots,  40  per  cent. 

OUR  PRODUCTS 


Uncoated  Armature  Tapes 


Sleevings 


Hose 


Frict'on  Tapes 


Red  Rope  Paper 


Press  Boards 


Rubber  Gloves 


THEM.W.  DUNTONCO. 

DDrt\/irhirkJS«C-  150-152  NIAGARA  o     . 

PROVIDENCE,  STREET  R.  I. 


"The  Electric  Vehicle  Hand-Book" 

SECOND     EDITION 


H.  C.  GUSHING,  Jr. 

Fellow  Am.  Inst.  Elec. 
Engrs.,  Publisher  of  "The 
Central  Station,"  the  offi- 
cial organ  of  the  Electric 
Vehicle  Association  of 
America, 

and 

FRANK  W.  SMITH 

Ex-President  Electric 
Vehicle  Association  of 
America  and  Vice  Pres. 
United  Electric  Light  & 
Power  Co.,  New  York: 

362  pages, 

fully  illustrated, 
flexible  cover, 
pocket  sizes, 

Price,  $2.00 


THE  ONLY  COMPLETE  AND  PRACTICAL  BOOK 
ON  THE  OPERATION,  CARE  AND  MAINTEN- 
ANCE OF  all  classes  OF  ELECTRIC  VEHICLES, 
their  Storage  Batteries,  Motors,  Controllers,  Tires  and 
Accessories. 

Sent  postpaid  to  any  address  on  receipt  of  $2.00. 
by 

H.  C.  GUSHING,  Jr. 

WORLD  BLDG.  NEW  YORK,  N.  Y. 


Sebco  Expansion  Bolts 

For  Fastening 

Conduit    and    Cables 


Made  of  Malleable  Iron — For  Heavy  Work 


Made  of  Lead  Composition — For  Small 
Fastenings  of  All  Kinds 


r 

The  Five  Points  Make  Drilling  Easy 

CATALOG  AND  SAMPLES  FREE 

Star    Expansion    Bolt   Company 

147   CEDAR  STREET,  NEW  YORK 

BRANCHES 

120  West  Lake  Street  579  Howard  Street 

Chicago  San   Francisco 


83 


The    SIMPLEX 

Magneto      Watchman's       Clock 
APPROVED  BY  UNDERWRITERS 


STYLE  A,   CAPACITY  25  STATIONS 
The  Record  is  made  on  rectangular  straight  24  hour  sheet 

Requires   no   attention   on   Sundays   and  holidays 
Compare  it  with  the  common  12  hour  round  dials.     Ask  for 
Catalog 

SIMPLEX  TIME  RECORDER  CO. 

1-4  Sanborn  Street  GARDNER,  MASS. 


TgERATEH  "POPULAR  QUALITY"  LINE 

"MADE  TO 
SELL  AND 
SATISFY" 

ONE  OF  THE         ty  TJJJ!? 

HUNDRED 

DESIGNS 

ON  WHICH 

WE  MAKE 

HOUR 
SHIPMENTS 


24 


Your     Name     on     Our 

Mailing  List  Will  Keep 

You  Supplied  with  Up- 

to-Date    Designs. 


Net 


NOT  WIRED 

FINISH 

BRUSHED  BRASS] 
and  BLACK    , 


Correctly  Displayed  This 
Design  Will  Bring  You 
Profitable  Business.  We 
Have  99  Other  Designs 
Equally  as  Attractive  on 
Which  We  Make  24  Hour 
Shipments. 


GAS  FIXTURE  &  BRASS  CO.,  308  High  St.,  Cleveland,  Ohio 


The  Star  Oval 
Split  Insulator 


Pat.    Dec.   5,   1905. 


For    the    use   of 

wire  without 

tying 


The  oval  shape  enables  the  hole  to  be 
placed  in  the  center  with  less  material  than 
generally  used,  and  holds  the  wire  securely 
when  in  place  by  means  of  the  curve  be- 
tween the  top  and  bottom. 

WRITE     FOR     OUR     CATALOGUE    AND    PRICES 


The  Star  Porcelain  Co. 

TRENTON,  N.  J. 


VULCAN 

Electric   Soldering 

TOOLS 

Heat  Quick  !  Stay  Hot  ! 

You  can  heat  Vulcan  Electric  Solder- 
ing Irons  in  less  time  than  it  takes  to 
get  a  gas  or  charcoal  furnace  started 
—and  they  stay  hot  all  the  time.  Their 
use  eliminates  fire  risk  and  increases 
output. 

Save  Time-Labor-Money 

Furnace  heated  coppers  are  old-fash- 
ioned— out-of-date.  The  Vulcan  Elec- 
tric Iron  does  soldering  quicker,  better 
and  cheaper.  There  are  eight  sizes  for 
all  kinds  of  work.  Each  tool  has' a  six- 
foot  cord  and  plug.  Tips  are  easily  re- 
placed when  worn  out. 

SOLD  BY  ALL  DEALERS 

WRITE  FOR  CATALOG  AND  FULL  INFORMATION 

Vulcan  Electric  Heating 
Company 

DEPT.  Z.  BUFFALO,  N.  Y. 


PHEN1XLITE 

The  Semi-Indirect  Light  of  the  Highest  Efficiency 


Pat.  Applied  for. 

A  Simple,  Economical,  Durable,  practically  Dustproof, 
absolutely  Glareless  Tungsten  Arc,  giving  a  large  volume 
of  illumination.  Light  is  reflected  from  lower  to  upper 
reflector,  thence  outward  and  downward. 

Try   it    for   better    Illumination.     Ask    for    Catalogue. 

THE  PHOENIX  GLASS  COMPANY 

NEW  YORK      BOSTON      CHICAGO       PITTSBURG 


THE   BEST   BRUSH 


service  for  any  condition  is 
derived  from  the  application 
of  the  proper  type  of 

Morganite 

or 


Battersea    Carbon 

brushes.      As  only  the  high- 
est   class    of  workmanship  is 
used    in  manufacturing 
after  thorough  investi- 
gation of  conditions  by 
engineers,      no      better 
brush  can  be  procured. 

The  Morgan  Crucible  Co.,  Ltd. 

114  Liberty  Street  New  York  City 


FRANKLIN  STEEL  WORKS 

FRANKLIN,  PENNA.,  U.  S.  A. 

New  York  Office :  30  Church  Street 

Denver  Office:  McPhee  Bldg. 

Minneapolis  Office:  Phoenix  Bldg. 


90 


REFLECTORS 


EFFICIENCY 
ARTISTIC  EFFECT 
SCIENCE  and 
DISTINCTIVENESS 


No.  1230  QJ2 

are  embodied  in  Haskins-Lucida  reflectors,  spheres  and 
hemispheres.  Lenticular  reflectors  for  high  efficiency  are 
acknowledged  the  best.  In  addition  to  the  scientific  lines 
of  reflectors,  namely,  Haskins-Lucida  and  Lenticular,  \ve 
make  a  complete  line  of  illuminating  glassware  in  cut, 
etched,  roughed  inside,  etc.,  etc. 

The  Haskins  Glass  Co. 

WHEELING,   W.  VA. 

BRANCHES 

New  York         Philadelphia         Chicago         Atlanta         Los  Angeles 


91 


Elblight  Lamps  and  Cables 


ARE  BEST  FOR 

Electrical 
Decorations 

EASY  TO 
INSTALL 

EASY  TO 
TAKE  DOWN 


Economical    and 
Artistic  for 

Inside  and 

Outside 

Effects 


Sold  or  Rented  at 
Attractive  Rates 


Send  for  Illustrated 

Catalog  and  Price 

List 


ELBLIGHT  COMPANY  OF  AMERICA 

133  W.  24th  St.         SSSi         NEW  YORK 


SINGLE  PHASE  MOTORS 

are  being  sold  and  recommended 
.by  such  a  large  number  of  Elec- 
trical Contractors  and  Central 
Station  Operators  because  they 
know  that  when  they  are  once 
properly  installed  they  will  give 
continued  satisfactory  service  to 
the  user. 

They  possess  those 
starting  and  oper- 
ating characteris- 
tics and  accurate 
rugged  construc- 
tion so  necessary 
for  the  develop- 
ment of  power 
business  and 
which  will  help  to  build  a  reputa- 
tion f or  Y  O  U  as  a  seller  of 
apparatus  possessing  that  much- 
sought  for  keep-a-running  quality 

%    to   40   H.   P.  25   to    140   cycles. 

Quick    shipments    always     from     26     Branch    Stocks. 

CENTURY  ELECTRIC  CO. 

New  York  Office:        Main  Office  and  Works: 

Hudson  Terminal,    19th,  Pine  and  Olive  Sts. 

30    Church    St.  St.    Louis,    Mo. 


93 


The  High  Grade  Insulation 
The  Copper  True  to  Gauge 
The  Extreme  Softness  of  Wire 
The  Quality  and  Reliability 


of 


M 


assachusetts 

AGNET  WIRE 


are  well  known 


Cotton  Covered 

Madf  Silk  Covered 

al1  Sizes  Enamel  Covered 


Massachusetts  Elec.  Mfg.  Co, 

WEST  LYNN,  MASS. 


Gas  and  Gasoline  Engines 


produce  electric  current  at  a  lower  cost 
than  by  steam  and  cheaper  than  other  makes  of 
internal  combustion  engines. 

They  are  world  renowned  for  fuel  economy  and 
low  cost  of  up-keep. 

Our  special  electric  types  operate  with  such  close 
regulations  that  the  cyclical  variation  in  speed  of 
the  engine  will  be  within  2  per  cent,  each  way  from 
mean  rated  speed  under  gradual  change  of  load. 

Send  for  Catalogue  No.  28  and  Bulletin  No.  10. 

THE    OTTO    GAS    ENGINE    WORKS 

3417  Walnut  St.,  Phil.,  Pa. 


er  Gas 


PREPARE  FOR  FIRE 


FIRE 
EXTINGUISHERS 

Are  the  Most  Efficient  Known 

The  Compound  Pyrene 

Is  a  non-conductor  of  electricity.  It  can 
be  used  with  perfect  safety  on  the  highest 
voltages. 

Does  not  deteriorate  with  age.  Therefore 
cost  of  maintenance  is  entirely  eliminated. 
Does  not  freeze.  It  is  therefore  service- 
able in  the  lowest  temperatures. 
Does  not  contain  acid,  alkali  or  moisture. 
It  is  therefore  non-damaging. 


Brass  and  nickel-plated  Pyrene.  Fire  Extinguishers  are  included 
In  the  lists  of  approved  fire  appliances  examined  under  the  re- 
quirements of  the  National  Board  of  Fire  Underwriters,  by 
the  Underwriters'  National  Electric  Association,  after  exhaustive 
tests  by  the  Underwriters'  Laboratories,  and  approved  for  use. 


The  Double-Acting  Pyrene  Pump 

Is  the  most  effective  method  of  getting  an  extin- 
guishing agent  on  a  fire.  Pyrene  Extinguishers  are 
strongly  constructed  of  the  very  best  materials  and 
carefully  tested  at  the  factory. 

Pyrene  Manufacturing  Co.,          New  York,  N.  Y. 


Aberdeen,   S,   D. 

Alton 

Anderson,  S.  C. 

Atlanta 

Baltimore 

Birmingham 

Bridgeport 

Boston 

Buffalo 


Charleston,  W.  Va. 

Charlotte*  N.  C. 

Chicago 

Cincinnati 

Cleveland 

Dayton 

Denver 

Detroit 

Duluth 


Fargo,   N.   D. 
Jacksonville 
Ivouisville 
Memphis 
Milwaukee 
New  Orleans 
Oklahoma  City 
Phoenix 


Philadelphia 
Pittsburg 
Richmond 
St.  Louis 
St.  Paul 
Salt  Lake  City 
San  Antonio 
York,  Neb. 


Pacific   Coast   Distributors:     Gorham   Fire   Apparatus   Co. 
San    Francisco  Los    Angeles  Seattle 

Distributors    for    Great    Britain    and    the    Continent: 
The    Pyrene    Co.,    Ltd.,    19-21    Great 'Queen    St.,    London,    W.    C. 


100 


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301240 


UNIVERSITY  OF  CALIFORNIA  lylBRAR 


